Thanks Matt. I experienced my first cold shower this week. I'd had no problems since my Rinnai was installed several years ago. I then noticed I was getting hot water intermittently. I quickly went to UA-cam to diagnose the problem and found your video. Performed the maintenance this morning and my heater is working great.
This was an exact replacement for the old one that lasted about 10 years. ua-cam.com/users/postUgkx7yWIKcrbA9KMHkGSfcgxW2lsjHT6B8Sh The top of my mitigation tube by my roofline was just a 90 elbow which allowed too much debris to fall down into the fan, eventually ruining it. Without this issue, I bet it would have kept running another 10 years. When I replaced this fan, I added an extra elbow joint so the top tube now it does a 180, which should solve that problem. The radon guys around here wanted to charge me a $300 diagnostic fee, then parts/labor (probably close to $600 total). I installed this all by myself in about an hour for the cost of the fan; it would probably be even easier/faster with two people. FYI the manufacturer's warranty greatly differs depending on whether you install it yourself (1 yr warranty) or have a licensed installer do it (10 yrs).
Overall good, glad you covered it. I'd say, as others have, the 1/6 horse at HF is cheap and works. Also you don't want to hook up a big pump and blow out anything. 1/6th horse is enough. My unit has 2 screens, owners should check for all filters/screens that can be cleaned/checked on. Finally, this is a good time to also check that the burner air intake and vent are clear, especially for indoor mounted units. Make sure that the air vents don't have leaves, or other debris blocking the air flow. Stay safe.
My Rinnai tankless was installed in 2012, and after watching your video I performed the procedure you showed, almost to a tee (but indoors). Worked flawlessly - you saved me $150.00! Thanks so much!
I have gone for 11 years. do you think its time for me to flush mine? my plumber wanted me to spend $2000 to replace it with another unit instead of doing this.
Howdy from Central Texas! I knew this would be a trustworthy video when I saw the HEB-Brand Vinegar. Thank you so much for saving me a call to the plumber! The instructions are straightforward to follow and work like a charm!
Thanks for you take on maintenance and other videos about the real world pluses and minuses on the tankless heaters. With smart phones, I figure you just put in an annual reminder (I do that with pretty much all my house/car maintenance routines) to flush/clean the unit and just work off that. Like you said, you can't do it too often and it's an easy to knock out rainy day task. I appreciate your candor and sharing knowledge.
It’s helpful to know “the why” it’s so important to descale your tankless water heater. Basically, the thin copper boiler tubes are directly immersed in 199,000 BTUs of flame in order to facilitate the flash boiling, this action causes the minerals in the water to separate, collect, and build-up onto the inside surfaces it the tubes, it actually looks just like cholesterol build up in ones arteries! The bad thing that happens is that as the “cholesterol” builds up so thick it forms an insulating layer between the boiler tubing and the water that is circulating through them. Then what happens is that the intense heat generated by the flames literally melts the copper tubing because the circulating water now can no longer transfer the heat to the water fast enough because of the insulating boundary produced from the buildup of minerals inside. The end result is a destroyed heat exchanger and you may as well buy yourself a brand new heater because you didn’t perform simple maintenance! :( ... I hope this helps...
@@donjohnson9893 Stainless steel will still build up the scale (cholesterol) inside the heat exchanger, making your system less efficient and eventually slowing down flow. You still have to do descale to have it work properly.
@@donjohnson9893 There are several advantages of copper. It is an extremely good thermal conductor and it is soft, which reduces stress from heat expansion, and also from the deposits, which have a different thermal expansion.
Those size of pumps are more like $50 at Lowes/Home Depot/Harbor Freight. It's useful to keep old washing machine hoses for this purpose, you are supposed to replace them every 5 years whether they are leaking or not. Then they can be used for stuff like this...I have like 5 sets. They also sell "cleaning vinegar" at most grocery stores that is a bit stronger than the cooking type. You have to look for it in the cleaning isle.
Yeah, was about to post that. I have a blue 1/8 HP submersible pump from HF and I think it was $30-40. I used it to pump water off my pool cover before I got a different cover that allowed water through.
Thank you for posting this Matt.. This is great information. We've had our Rinnai unit now for 4 years, and we absolutely love it. Since its inception we've been flushing with White Vinegar. The unit we have, Rinnai actually denotes not to use chemicals to flush out the system, but I know several owners are using chemicals with success..... One thing we had to adjust after our Rinnai system was installed ~~ Our dishwasher immediately started acting up. It would run 2X it's normal time, and it was not sanitizing items.... After talking with Whirlpool (maker of our dishwasher) we ended up adjusting the Rinnai's temperature from 120 degrees to 135 degrees... After that was changed,, everything went back to normal............. Thanks again for sharing this with the world.................
Excellent step by step instructions. Got to check if my Navien Tankless is a stainless system. And note about Vinegar: don’t dump it in your grass unless you’re looking to kill it like my wife did ours.
I am an HVAC contractor wholly ignorant to tankless PM. I recently noticed our water softener had failed and was very concerned about months of use without protection. Replaced the water softener. Reviewing some of your videos and this one gave me assurance to PM the unit. I already have an acid pump (I use it now to drain the hot tub, Hah!) and have plugged in on my calendar to descale my unit annually. Thank you for keeping it simple!
Thanks so much for this Matt. I have a Rinnai in a cabin my wife and I just bought. Given the hardness of the well water, I knew it would need this procedure. Worked perfectly - and I was so happy to have done it that I went home and performed on my 6 year old Takagi at home. Same great results! Thank you!
Just completed flushing out my Takagi Tankless water heater and it was very easy to complete after watching your video. THANK YOU as it was really needed, and your detailed instructional video was very easy to follow. Keep all the good Videos coming!!!!
Here is Tucson, AZ, with extremely hard city water, I flush once a year (with a person household). My Rinnai manual does recommend using 4 gallons of vinegar in the bucket. I guess it keeps its strength up during the flush with more vinegar volume.
Did my Rinnai, very simple and a good video. Of note - Rinnai manual says to use 4 gallons of undiluted food grade vinegar for 1 hour not the 1 gallon for 45 minutes that Matt said. 4 gallons is much more likely to clean everything out and adds just a few dollars to the total process.
Nice Video. I clean mine once a year. Here in Indiana, our water is typically very hard with lime. Most plumbers here will not install a tankless unless there is a water softener to soften the water before it goes through the tankless.
I’ve flushed my tankless water heater before but didn’t know about the screen cleaning. I wished I would have watched this first as I took a lot longer to do it because I was figuring out how to do it as I went. Great information. Thanks.
While Rinnia does just recommend just turning off the gas because the units will try to cycle the internal cold valve closed if a power loss occurs with the small amount of energy held in its power supply. The way to get around it if you want to cut power is to open relief valve and while unit is fired cut the power. It won't have the time to cycle valve before power is lost and as long as u run the water a few more seconds you will safely remove any heat in the exchanger the fan would normally blow out at the end of the burn cycle
Did this today. 1st time. House is only 1.5 years old. Went off without a hitch, followed the video start to finish. I was surprised how much junk was in the screen. Sand and calcium mostly but also some other stuff. Pressure is much better now. Gonna clean it more often. Thanks Matt!!!
Something to keep in mind is copper transfers heat 25 times better than stainless steel. So you will use more electricity/gas to heat a unit with stainless steel. Also stainless steel is known to become brittle after many cycles of being heated and cooling compared to copper. I did metal fabrication for many years.
Something else to keep in mind is the engineers designing the product are also aware of this; so the design is compensated by increasing the surface area, reducing the thickness of the tubing, etc. Stainless steel is 24 times less thermally conductive than copper, stainless steel heat exchangers are not.
Glad I saw this. Was debating on getting one. Mine would be tucked in my basement with no drain in the floor anywhere. Would need to get a little creative with the maintenance.
Great video! I had a Renai installed when I remodelled couple of years ago. I live alone but I’m in Florida and the water here is extremely harsh. I am over due for a flush. I love the unit. Mine is a gas unit.
Thank you for the thorough how-to video. Your videos are always great! I wish I would've seen them before I started a still-unfinished gutted remodel 10 years ago with absolutely zero construction experience.
Great video. I've had a Navien tankless for a little over two years now and had a water softener system put in at the same time. Love the benefits of having soft water and I did a flush on my heater last December just to be proactive.
Josh Aguirre you also have the stainless steel burn coils. When Navien come out they did not advise flushing them at all. After a few years went by. Then they started advising every 2 years. The scale really does not stick to stainless steel. The Navien is the only tankless I advise people to install. If they want to purchase some other brand the warranty falls back on them. All I have to warranty is the install. I’ve supplied and installed 100’s of Navien tankless. This tankless was a Hack job installation!!!
James Gleason so what are you trying to say to me. Do you think I don’t know anything about soft water? I don’t use soft water because of the salt that comes along with them. I have a bad heart. So salt is not my friend..
Thank you Matt great video. Now I need to find another one that shows me how to service the inside of the unit itself. If I can find one of those one RL75 unit as detailed and useful as your video I’ll be good to go. Again thx for the video, great job and very simple.
@@buildshow My Rinnai manual talks about opening the unit up, spraying canned air, checking the blue flame, etc. Is that necessary each time along with the flushing? Or should I have a certified plumber do that part?
Nice video. Got 3 things.1 That's an expensive work bench you have there. 2 When we acidized heat exchangers we always back flowed the acid. Is there a reason for flushing with the flow direction? 3 Also we would use some baking soda during the pump flush to neutralize the acid.
Great video. You did not "explicitly" state that you needed to plug the water heater back in for the interlock to permit water flow. I figured out that's what you were referring to when the unit was beeping. Also reiterate to clean all water and air screen filters.
The exterior install is a real eyesore. This is why you need to design a mechanical room that can contain all the home's systems in an organized, well thought through way.
Rinnai provides a sleek cover for the exposed pipes at the bottom with the purchase of a unit. Some people choose not to use them. In my opinion, this has a negative effect on the appearance of the installation.
The pump in bucket system is fantastic, in the UK they sell a machine called a power flush which retailers for around 2200$. Also manufacturers of combination boilers have decided to block off access to the underside units to be able to simply connect this sort of device so a simple modification would be necessary.
I had one installed just last year. Same brand likely different model. I live in Arkansas where we get maybe 2-3 weeks below freezing. We haven’t seen a below freezing day yet. But I have my lines below the unit in a cover with a thermostat controlled heat strip on the lines. I not worried out the lines as much as I’m worried about the heating core. I took a gamble and installed an outside unit. Fingers crossed I didn’t make a mistake. I needed the space inside. *** update*** I was so concerned that since I live in a Arkansas where we do get below freezing I contacted Rinnai. My Model is the RL75eN This is their quoted reply below. This took a massive weight off my shoulders on worrying it was going to freeze up. “A Rinnai tankless water heater features built-in freeze protection, so it will remain in operation in temperatures as low as -30℉. In order to use this feature, you must have both power and gas run to the unit. In addition, the pipes into the tankless water heater must be heat traced and insulated to protect them from freezing. A Rinnai-certified contractor or approved plumber will follow installation recommendations so your unit can operate optimally, even in cold weather.”
Mark Eckelkamp our tank was in an indoor closet , so we actually gained space with the tankless . Our model has stainless steel guts . Should last a lifetime .
@@MARKE911 I was wondering about cold weather, SW Missouri here. Looking at doing something different that a 40 gal tank that's 20 plus years old. Would like some REAL hot water plus get the Misses off my rear about not being able to use her jacuzzi tub.
BT B they sell indoor units, you have to change the duct size if your vent up and out but the higher efficiency units you can use PVC. I’m really pleased with mine. You get more cold weather than we do by far. I have an indoor thermostat where I can adjust the temperature of the water based on the incoming water temperature I can turn it off from there as well. The #1 downfall is waiting (or wasting) the water to get to the temperature you desire. My unit has the ability to install a recirculating pump so it doesn’t waste water but I opted out as water is way cheaper than gas at least for me here. I wish I could post pictures on here. It would be nice.
I've owned my house over four years and never knew I had to clean my tank-less water heater until I ran across a UA-cam video a few months ago. I got all the supplies and went through the task of flushing the unit. Turns out that my unit was not in bad shape after four years. You can tell if you have a lot of scale by the color of the vinegar. The more scale you have the more blue the vinegar turns.
This is good because I need a new water heater very soon because after about 10 minutes the water isn't even hot anymore and it just gets cooler and cooler.
I’d bet my left shoe that either the lower element is burned out or the upper thermostat switch is bad. I would just replace both elements and both thermostats. Like $40.
@@paulmccoy2908 Agreed! I started running out of how water when my tank heater was just over a year old. The lower element had become caked in deposits and shorted itself out. Changed it to a low-density looped-over coil for $15 and all was well again. I prefer tanks, they are cheaper up front and to repair, just flush them once a year and they'll be good for 10-20+ years.
Thanks Matt! Just performed this on my Rinnai (household of three adults) and it went flawless (other than the submersible pump not having the right adapter for my washing machine hoses). Had to improvise. All done! Thanks again.
Thanks for the tip about rinsing the pump. I never rinsed mine. Now I need a new one :( The Noritz instructions tell you to keep the power on while you are descaling. I guess there are slightly different procedures for different units.
Also usable (food grade) citric acid. Works great on calcium and magnesium deposits, is less aggressive to metal than vinegar, cheap, non toxic, no smell, no taste except sour
@@capsman4747 Many descaling agents are made of citric acid, you can buy it in gastronomic shops or like everything else online. It comes as a powder like salt or sugar. (it is the stuff on sour candy)
Just did this to my heater after quite a few years of use thanks to the urging of this video. I used the Flowaid mixed with a single gallon of water in a 5 gallon bucket. Don’t use rubber hoses like I did, the cleaner tears it up. Use stainless for sure! Be prepared to clean that prescreen a few times too. When done flushing dump the bucket empty and allow fresh water in from the street but NOT into your pipes, keep the drain hose from the hot side in the bucket. This will remove the cleaner easily, I did this with 3 bucket loads. Make sure you also flush the pump and hoses for your next use as this stuff will eat those up if left sitting I’m sure! Hard to tell how much crap I got out of mine with the hoses breaking down but I’m certain I got things cleaner than before and it took less than two hours.
Very informative. I'm in the market for a Combi Unit and want to know everything first. If you're anything like me, it would be helpful to have a sticker to mark the date of each maintenance.
Instead of pouring the vinegar onto the ground, use it to clean out the drains in the house. Pour about 2 cups down the drain and follow with a 1/2 cup baking soda, let it work for 15 to 30 minutes then run hot water for about 5 minutes or less. This helps remove the buildup in the pipes and can help keep odors at bay.
You should do a video on electric tankless heaters as well. Very common outside of the US, and becoming more common in the US (not everyone has or likes natural gas).
How are you liking your tankless? I am currently researching and considering making the same switch. My current electric tank is up in my attic. That's a beast in itself. A company has suggested one of these outside my home.
@@jmramirez0609 so far so good. We opted to not use an automatic recycling system-it senses the water temperature drop in the pipe and recirculates hot water. We chose to install push buttons in a couple of locations that will do that as needed.
FYI I use a stainless steel water distiller which is basically a water boiler and it holds 1 1/2 gal of water and even though its stainless steel it still collects A LOT of mineral deposits and other water bourn contaminants despite being stainless steel so be aware of that and I have to clean it the same way you clean the tankless water heater by flushing it with vinegar as well. I was thinking that a pre filter in the water supply could ease up on the flushing prosses.
Thanks so much for your indepth instruction. I have an all electric home and will most likely not install a tankless. When it comes time to replace my unit I will most likely buy a hybrid. Could you do a video on pros and cons of separate tank and all in one units? Also if there is any kind of special maintenance needed for hybrid systems. I love your channel and anything energy saving and or making our homes longer lasting.
Something to think about. My Rinnai water heater (10 years old) recently developed a pinhole leak in the cold water cooper tube inside the unit, along with green mineral deposits surrounding the hole. This suggests that there has been corrosion inside the tube, and more holes are a distinct possibility. My cabin is on a well, quite hard water. When I'm gone, the water sits in the tube, and I think that over time that has resulted in the corrosion I'm seeing. I'm planning to replace the unit, but I think that in the next decade I'll plan on draining the unit when I'm away, and hope that addresses the problem.
If you dont live there a lot, put in a regular tank heater if you have the room. They're a whole lot easier to flush of minerals and build-up if you have really hard water, plus elements are $15 if they cake up with deposits.
Matt... Just getting thru this southern freeze and it looks as though our Rinnai R47 is leaking, near top coils - haven't taken apart, but obvious leak. Do you think the unit can be salvaged / repaired, or done for and needs to be replaced. I've had for 6 years and thanks to your video, I just learned it needed maintenance... Never done it! We've had low water pressure due to MUD district and apparently 'junk' coming in lines... So obviously several potential issues.
Matt, helpful video. But we all know this rarely, if ever, gets done unless scale becomes an issue (like clogging up shower mixing valves or spray heads)
Who installed that unit? Is that crappy quality to be expected every time? I figured they would be hardwired and have the supply lines not going at an angle across the wall. It seems like the plumber didnt really put much care into it
moncorp1 Inc Oh is that what it is? I figured if I pay a guy a grand to install something he’ll put a little pride into it. It is in fact his whole profession
Cisco8484 I’d agree that the scale is from dissolved minerals, but it should be formed along the wall of the boiler where that mineral rich water is flash boiling
@@Cisco8484 The scales form on the boiler and then break off after accumulating for awhile. The big chunks of minerals are what causes problems in your plumbing downstream. If it were just dissolved minerals there would be no need to descale.
I couldn't help but notice you did not service the combustion side of this unit. This should also be done every year in accordance with a flush as the burners, flame rods, and heat exchanger all get very dirty. The gas pressure should also be checked and set accordingly if possible. Rinnai has a service info sheet inside of the door of all of their units that tells you all of the specs. for setting the gas pressure. This video should just be titled how to flush your tankless water heater.
You did not mention that the manufacture recommends 4 gallons of 5% vinegar solution per flush. Five percent is the normal strength you will find though some discount brands may be diluted down to 3%.
Helpful Tip. If you question your hardness rating and have a public water supply contact your local water utility they will be able to provide you the answer, or look at the annual Water Quality Report sometimes called the CCR - Consumer Confidence Report. They are required by the EPA to have that available to all customers and update it every year. If your water utility gets its water from wells then the Hardness level will be higher if they get the water from a lake or any other above ground source it will be lower or “softer” Water hardness levels are considered as following 0-75 mg/L -Soft 75-150 mg/L -Slightly Hard 150-300 mg/L - Moderately Hard 300 + mg/L -Very Hard mg/L = milligrams per Liter other wise known as PPM or parts per million . yes in the water industry we don’t use the standard imperial measurements but if converted it would be as the following 0-1 Grains per Gallon - Soft 1-3.5 Grains - Slightly Hard 3.5 - 7 Grains - Hard 7 - 10 Grains - Moderately Hard 10 + Grains - Very Hard Here in Central Arkansas we have some of the best Water in the United States. The hardness of the water provided by Central Arkansas Water is between 1.0-1.7 grains/gallon or 17-29 mg/L. This is considered a “soft” water. If you made it this far I’m impressed. I’m a licensed D-4 Water Nerd. “Keeping the water Clean and Flowing” -ME
You'd be amazed at just how many people assume that, A hot water system DOES NOT NEED ANY MAINTENANCE! Even those who build homes & remodellers. The old style-Hot water Tanks need flushed yearly if you want them to last! Or even twice per year would be best! Especially if one has hard water & an older tank style water heater.
The US has used tank heaters since forever, little maintenance was required so nobody really thought about them. With tankless, every owner needs to relearn how to deal with them. Builders and remodelers arent going to tell people their new unit/house needs *more* maintenance either.
If you have hard water from the city, why not release the vinegar in the system into your water lines and flush them and your faucets as well? Take off all the aerators and allow the in-line scale build up to flush from all the water lines?
I looked at your first video from 2013 and this one, and there is a conflict about the power. A few other videos say keep the power on, but you say to unplug it. Does it matter if the power is on or not? Thanks for all your videos. You have no idea how much you've helped us here in Charlotte North Carolina.
I got a Takagi installed 14 years ago. Never flushed it yet. My water is filtered before the softener then filtered again before the Takagi. No problems. I still need to add those valves .. Because I love more maintenance lol
Seeing this kit on the outside of your house I can see why that winter storm in Texas caused so much chaos!
Thanks Matt. I experienced my first cold shower this week. I'd had no problems since my Rinnai was installed several years ago. I then noticed I was getting hot water intermittently. I quickly went to UA-cam to diagnose the problem and found your video. Performed the maintenance this morning and my heater is working great.
How long did you wait before you flushed it? And how long did you end up letting the pump flush it?
This was an exact replacement for the old one that lasted about 10 years. ua-cam.com/users/postUgkx7yWIKcrbA9KMHkGSfcgxW2lsjHT6B8Sh The top of my mitigation tube by my roofline was just a 90 elbow which allowed too much debris to fall down into the fan, eventually ruining it. Without this issue, I bet it would have kept running another 10 years. When I replaced this fan, I added an extra elbow joint so the top tube now it does a 180, which should solve that problem. The radon guys around here wanted to charge me a $300 diagnostic fee, then parts/labor (probably close to $600 total). I installed this all by myself in about an hour for the cost of the fan; it would probably be even easier/faster with two people. FYI the manufacturer's warranty greatly differs depending on whether you install it yourself (1 yr warranty) or have a licensed installer do it (10 yrs).
Overall good, glad you covered it.
I'd say, as others have, the 1/6 horse at HF is cheap and works. Also you don't want to hook up a big pump and blow out anything. 1/6th horse is enough. My unit has 2 screens, owners should check for all filters/screens that can be cleaned/checked on. Finally, this is a good time to also check that the burner air intake and vent are clear, especially for indoor mounted units. Make sure that the air vents don't have leaves, or other debris blocking the air flow.
Stay safe.
My Rinnai tankless was installed in 2012, and after watching your video I performed the procedure you showed, almost to a tee (but indoors). Worked flawlessly - you saved me $150.00! Thanks so much!
Yeah I'm guilty I have never done mine even though I know I should out of site out of mind
This video will help us too. My local plumber wants to charge $700, every two years. Maybe he's saving for a Porche with those prices?
I have gone for 11 years. do you think its time for me to flush mine? my plumber wanted me to spend $2000 to replace it with another unit instead of doing this.
Howdy from Central Texas! I knew this would be a trustworthy video when I saw the HEB-Brand Vinegar. Thank you so much for saving me a call to the plumber! The instructions are straightforward to follow and work like a charm!
Thanks for you take on maintenance and other videos about the real world pluses and minuses on the tankless heaters. With smart phones, I figure you just put in an annual reminder (I do that with pretty much all my house/car maintenance routines) to flush/clean the unit and just work off that. Like you said, you can't do it too often and it's an easy to knock out rainy day task. I appreciate your candor and sharing knowledge.
It’s helpful to know “the why” it’s so important to descale your tankless water heater. Basically, the thin copper boiler tubes are directly immersed in 199,000 BTUs of flame in order to facilitate the flash boiling, this action causes the minerals in the water to separate, collect, and build-up onto the inside surfaces it the tubes, it actually looks just like cholesterol build up in ones arteries! The bad thing that happens is that as the “cholesterol” builds up so thick it forms an insulating layer between the boiler tubing and the water that is circulating through them. Then what happens is that the intense heat generated by the flames literally melts the copper tubing because the circulating water now can no longer transfer the heat to the water fast enough because of the insulating boundary produced from the buildup of minerals inside. The end result is a destroyed heat exchanger and you may as well buy yourself a brand new heater because you didn’t perform simple maintenance! :( ... I hope this helps...
Thanks for the additional info
Steve Ewing or you could buy stainless steel instead of thin copper .,
@@donjohnson9893 Stainless steel will still build up the scale (cholesterol) inside the heat exchanger, making your system less efficient and eventually slowing down flow. You still have to do descale to have it work properly.
@@donjohnson9893 There are several advantages of copper. It is an extremely good thermal conductor and it is soft, which reduces stress from heat expansion, and also from the deposits, which have a different thermal expansion.
Always, Always install a filter before
Any brand of tankless.
Those size of pumps are more like $50 at Lowes/Home Depot/Harbor Freight. It's useful to keep old washing machine hoses for this purpose, you are supposed to replace them every 5 years whether they are leaking or not. Then they can be used for stuff like this...I have like 5 sets. They also sell "cleaning vinegar" at most grocery stores that is a bit stronger than the cooking type. You have to look for it in the cleaning isle.
The vinager I find is 5% acid, and the one he seems to be using is 9%, wonder what cleaning threshold is.
Yeah, was about to post that. I have a blue 1/8 HP submersible pump from HF and I think it was $30-40. I used it to pump water off my pool cover before I got a different cover that allowed water through.
Never seen that at a grocery store but I know Lowe's sell I think 20% acid vinegar. It's more expensive but not too bad
@@Eric998765 10%
Thank you for posting this Matt.. This is great information. We've had our Rinnai unit now for 4 years, and we absolutely love it. Since its inception we've been flushing with White Vinegar. The unit we have, Rinnai actually denotes not to use chemicals to flush out the system, but I know several owners are using chemicals with success..... One thing we had to adjust after our Rinnai system was installed ~~ Our dishwasher immediately started acting up. It would run 2X it's normal time, and it was not sanitizing items.... After talking with Whirlpool (maker of our dishwasher) we ended up adjusting the Rinnai's temperature from 120 degrees to 135 degrees... After that was changed,, everything went back to normal............. Thanks again for sharing this with the world.................
No hot water…watched vid…did process. Hot water.
You earned your like, Matt.
Excellent step by step instructions. Got to check if my Navien Tankless is a stainless system. And note about Vinegar: don’t dump it in your grass unless you’re looking to kill it like my wife did ours.
Thank you for this video! You saved me $195 to have someone do it. I have AO Smith Tankless Water heater. Very easy to follow!🙂👍👍
I am an HVAC contractor wholly ignorant to tankless PM. I recently noticed our water softener had failed and was very concerned about months of use without protection. Replaced the water softener. Reviewing some of your videos and this one gave me assurance to PM the unit. I already have an acid pump (I use it now to drain the hot tub, Hah!) and have plugged in on my calendar to descale my unit annually. Thank you for keeping it simple!
Thanks so much for this Matt. I have a Rinnai in a cabin my wife and I just bought. Given the hardness of the well water, I knew it would need this procedure. Worked perfectly - and I was so happy to have done it that I went home and performed on my 6 year old Takagi at home. Same great results! Thank you!
Putting a descaling filter on the cold side helps alot.
I’ve had a tankless water heater for about 12 years and haven’t needed to do this rescale process because I have a home water softener!
Just completed flushing out my Takagi Tankless water heater and it was very easy to complete after watching your video. THANK YOU as it was really needed, and your detailed instructional video was very easy to follow. Keep all the good Videos coming!!!!
Here is Tucson, AZ, with extremely hard city water, I flush once a year (with a person household). My Rinnai manual does recommend using 4 gallons of vinegar in the bucket. I guess it keeps its strength up during the flush with more vinegar volume.
Did my Rinnai, very simple and a good video. Of note - Rinnai manual says to use 4 gallons of undiluted food grade vinegar for 1 hour not the 1 gallon for 45 minutes that Matt said. 4 gallons is much more likely to clean everything out and adds just a few dollars to the total process.
Nice Video. I clean mine once a year. Here in Indiana, our water is typically very hard with lime. Most plumbers here will not install a tankless unless there is a water softener to soften the water before it goes through the tankless.
I’ve flushed my tankless water heater before but didn’t know about the screen cleaning. I wished I would have watched this first as I took a lot longer to do it because I was figuring out how to do it as I went. Great information. Thanks.
good information & explained very well, thank you. I'm a retired plumber and still learning! 👍👍
While Rinnia does just recommend just turning off the gas because the units will try to cycle the internal cold valve closed if a power loss occurs with the small amount of energy held in its power supply. The way to get around it if you want to cut power is to open relief valve and while unit is fired cut the power. It won't have the time to cycle valve before power is lost and as long as u run the water a few more seconds you will safely remove any heat in the exchanger the fan would normally blow out at the end of the burn cycle
I have a Rheem and for the life of me I cannot get flush to flow out of the hot water side. Maybe this is why?
Thanks, going to make sure we got this for our new install coming up! Amazon has a set of the valves needed for $59 if needed!
Did this today. 1st time. House is only 1.5 years old. Went off without a hitch, followed the video start to finish. I was surprised how much junk was in the screen. Sand and calcium mostly but also some other stuff. Pressure is much better now. Gonna clean it more often. Thanks Matt!!!
Heads up, on Noritz brand there is a jumper labeled inside of the unit you have to connect to flush the unit.
Depending what noritz heater you have installed
All units should have full instructions under 'Maintenance' heading.
Vinegar will kill your grass. Avoid where you dump it.
Something to keep in mind is copper transfers heat 25 times better than stainless steel. So you will use more electricity/gas to heat a unit with stainless steel. Also stainless steel is known to become brittle after many cycles of being heated and cooling compared to copper. I did metal fabrication for many years.
Something else to keep in mind is the engineers designing the product are also aware of this; so the design is compensated by increasing the surface area, reducing the thickness of the tubing, etc. Stainless steel is 24 times less thermally conductive than copper, stainless steel heat exchangers are not.
Glad I saw this. Was debating on getting one. Mine would be tucked in my basement with no drain in the floor anywhere. Would need to get a little creative with the maintenance.
Awesome, I got one in the spring, so Ill be prepped for then
Great video! I had a Renai installed when I remodelled couple of years ago. I live alone but I’m in Florida and the water here is extremely harsh. I am over due for a flush. I love the unit. Mine is a gas unit.
Thank you for the thorough how-to video. Your videos are always great! I wish I would've seen them before I started a still-unfinished gutted remodel 10 years ago with absolutely zero construction experience.
Great video. I've had a Navien tankless for a little over two years now and had a water softener system put in at the same time. Love the benefits of having soft water and I did a flush on my heater last December just to be proactive.
Josh Aguirre you also have the stainless steel burn coils. When Navien come out they did not advise flushing them at all. After a few years went by. Then they started advising every 2 years. The scale really does not stick to stainless steel.
The Navien is the only tankless I advise people to install. If they want to purchase some other brand the warranty falls back on them. All I have to warranty is the install.
I’ve supplied and installed 100’s of Navien tankless.
This tankless was a Hack job installation!!!
@@ltsgarage7780 Soft water has little healthy minerals such as calcium and magnesium and can be unsuitable to drink.
James Gleason so what are you trying to say to me. Do you think I don’t know anything about soft water?
I don’t use soft water because of the salt that comes along with them. I have a bad heart. So salt is not my friend..
@@ltsgarage7780, Check out State Water Heaters, Tankless X3 Scale Prevention Technology.
Thank you Matt great video. Now I need to find another one that shows me how to service the inside of the unit itself. If I can find one of those one RL75 unit as detailed and useful as your video I’ll be good to go. Again thx for the video, great job and very simple.
Congrats on 700K subscribers, Matt!
WooHoo! Thanks
@@buildshow My Rinnai manual talks about opening the unit up, spraying canned air, checking the blue flame, etc. Is that necessary each time along with the flushing? Or should I have a certified plumber do that part?
Learn a lot from this video. Thank you so much and keep up the great work,easy to understand.
Thanks! I had one of these put in our new construction so I'm glad I know how to maintain it now.
Nice video. Got 3 things.1 That's an expensive work bench you have there. 2 When we acidized heat exchangers we always back flowed the acid. Is there a reason for flushing with the flow direction? 3 Also we would use some baking soda during the pump flush to neutralize the acid.
so descale then add scale back in????????????
Great video. You did not "explicitly" state that you needed to plug the water heater back in for the interlock to permit water flow. I figured out that's what you were referring to when the unit was beeping. Also reiterate to clean all water and air screen filters.
The exterior install is a real eyesore. This is why you need to design a mechanical room that can contain all the home's systems in an organized, well thought through way.
Rinnai provides a sleek cover for the exposed pipes at the bottom with the purchase of a unit. Some people choose not to use them. In my opinion, this has a negative effect on the appearance of the installation.
Not all of us have room for an interior unit.
Jaime from lecanto Florida thank you was a great video to do my tankless water heater cleaning 👍
The pump in bucket system is fantastic, in the UK they sell a machine called a power flush which retailers for around 2200$. Also manufacturers of combination boilers have decided to block off access to the underside units to be able to simply connect this sort of device so a simple modification would be necessary.
Straight forward and very helpful tutorial. Thank you
Never seen an outdoors install like that before .
I had one installed just last year. Same brand likely different model. I live in Arkansas where we get maybe 2-3 weeks below freezing. We haven’t seen a below freezing day yet. But I have my lines below the unit in a cover with a thermostat controlled heat strip on the lines. I not worried out the lines as much as I’m worried about the heating core. I took a gamble and installed an outside unit. Fingers crossed I didn’t make a mistake. I needed the space inside.
*** update***
I was so concerned that since I live in a Arkansas where we do get below freezing I contacted Rinnai. My Model is the RL75eN
This is their quoted reply below. This took a massive weight off my shoulders on worrying it was going to freeze up.
“A Rinnai tankless water heater features built-in freeze protection, so it will remain in operation in temperatures as low as -30℉. In order to use this feature, you must have both power and gas run to the unit. In addition, the pipes into the tankless water heater must be heat traced and insulated to protect them from freezing. A Rinnai-certified contractor or approved plumber will follow installation recommendations so your unit can operate optimally, even in cold weather.”
Mark Eckelkamp our tank was in an indoor closet , so we actually gained space with the tankless . Our model has stainless steel guts . Should last a lifetime .
@@MARKE911 I was wondering about cold weather, SW Missouri here. Looking at doing something different that a 40 gal tank that's 20 plus years old. Would like some REAL hot water plus get the Misses off my rear about not being able to use her jacuzzi tub.
BT B they sell indoor units, you have to change the duct size if your vent up and out but the higher efficiency units you can use PVC. I’m really pleased with mine. You get more cold weather than we do by far. I have an indoor thermostat where I can adjust the temperature of the water based on the incoming water temperature I can turn it off from there as well. The #1 downfall is waiting (or wasting) the water to get to the temperature you desire. My unit has the ability to install a recirculating pump so it doesn’t waste water but I opted out as water is way cheaper than gas at least for me here. I wish I could post pictures on here. It would be nice.
Quite common in Southern California. No venting issues
Oh boy. We have incredibly soft water here but I never even thought to do this. Been installed for 6 years....better look into this.
My Bosch unit from 2008 had never been cleaned. Maybe I have a weekend project 👀🤔🤷🏻♂️
I've owned my house over four years and never knew I had to clean my tank-less water heater until I ran across a UA-cam video a few months ago. I got all the supplies and went through the task of flushing the unit. Turns out that my unit was not in bad shape after four years. You can tell if you have a lot of scale by the color of the vinegar. The more scale you have the more blue the vinegar turns.
This is good because I need a new water heater very soon because after about 10 minutes the water isn't even hot anymore and it just gets cooler and cooler.
Flush your current tank. Probably filled with scale.
I’d bet my left shoe that either the lower element is burned out or the upper thermostat switch is bad. I would just replace both elements and both thermostats. Like $40.
Or just buy a new house, and your problem might be solved. Probably not, but enjoy the new house!
@@paulmccoy2908 Agreed! I started running out of how water when my tank heater was just over a year old. The lower element had become caked in deposits and shorted itself out. Changed it to a low-density looped-over coil for $15 and all was well again.
I prefer tanks, they are cheaper up front and to repair, just flush them once a year and they'll be good for 10-20+ years.
Thanks Matt! Just performed this on my Rinnai (household of three adults) and it went flawless (other than the submersible pump not having the right adapter for my washing machine hoses). Had to improvise. All done! Thanks again.
Thanks for the tip about rinsing the pump. I never rinsed mine. Now I need a new one :(
The Noritz instructions tell you to keep the power on while you are descaling. I guess there are slightly different procedures for different units.
you have a great variety of content on your channel and vids like this are a super addition to all the rest
Also usable (food grade) citric acid. Works great on calcium and magnesium deposits, is less aggressive to metal than vinegar, cheap, non toxic, no smell, no taste except sour
Citric acid tends to be better for gaskets/rubber/plastics than vinegar too!
Where do you buy citric acid? With vinegar, it turns green from dissolving scale.
@@capsman4747 Many descaling agents are made of citric acid, you can buy it in gastronomic shops or like everything else online. It comes as a powder like salt or sugar. (it is the stuff on sour candy)
@@matekochkoch Thanks for the info. As for pumps, the cheapest pond pumps work great. That's what I use.
Thanks so much for this video Matt! Flawless instructions and your advice to flush everything at the end was great advice.
This was very helpful I have been debating and this convinced me to avoid a thankless heater lol
In the UK boiler services goes a lot more in depth with cleaning inside, the burner and fan is removed and the heat exchangers cleaned.
Amazon pretty much has a kit with pump, hoses, and flushing fluid for about $90. Sold! Arrives in one day for Prime members too.
Just did this to my heater after quite a few years of use thanks to the urging of this video. I used the Flowaid mixed with a single gallon of water in a 5 gallon bucket. Don’t use rubber hoses like I did, the cleaner tears it up. Use stainless for sure! Be prepared to clean that prescreen a few times too. When done flushing dump the bucket empty and allow fresh water in from the street but NOT into your pipes, keep the drain hose from the hot side in the bucket. This will remove the cleaner easily, I did this with 3 bucket loads. Make sure you also flush the pump and hoses for your next use as this stuff will eat those up if left sitting I’m sure! Hard to tell how much crap I got out of mine with the hoses breaking down but I’m certain I got things cleaner than before and it took less than two hours.
Thanks for the info Matt! 😃👍🏻👊🏻
would love to see one of those stainless units busted open after like 5 and 10 years of use.
Very informative. I'm in the market for a Combi Unit and want to know everything first. If you're anything like me, it would be helpful to have a sticker to mark the date of each maintenance.
Instead of pouring the vinegar onto the ground, use it to clean out the drains in the house. Pour about 2 cups down the drain and follow with a 1/2 cup baking soda, let it work for 15 to 30 minutes then run hot water for about 5 minutes or less. This helps remove the buildup in the pipes and can help keep odors at bay.
Hi
You should do a video on electric tankless heaters as well. Very common outside of the US, and becoming more common in the US (not everyone has or likes natural gas).
You should also open the unit and clean the burner, flame rods and igniter
Worked for me - thanks for the howto!
Thanks Matt, just had one of these installed replacing two electric hot water heaters!
How are you liking your tankless? I am currently researching and considering making the same switch. My current electric tank is up in my attic. That's a beast in itself. A company has suggested one of these outside my home.
@@jmramirez0609 so far so good. We opted to not use an automatic recycling system-it senses the water temperature drop in the pipe and recirculates hot water. We chose to install push buttons in a couple of locations that will do that as needed.
FYI I use a stainless steel water distiller which is basically a water boiler and it holds 1 1/2 gal of water and even though its stainless steel it still collects A LOT of mineral deposits and other water bourn contaminants despite being stainless steel so be aware of that and I have to clean it the same way you clean the tankless water heater by flushing it with vinegar as well. I was thinking that a pre filter in the water supply could ease up on the flushing prosses.
Don't forget to clean your intake air filter screen while you're at it.
Clean right after installation because soldering flux can stick in filter and cause hot/cold water sandwich.
Is there a video to show where the intake air filter is? I have AO Smith brand.
you make excellent informative videos Matt, thank you
Excellent video, Matt! Thanks for sharing the knowledge!
Thanks Matt and crew for all the great videos and info!
Thanks so much for your indepth instruction. I have an all electric home and will most likely not install a tankless. When it comes time to replace my unit I will most likely buy a hybrid. Could you do a video on pros and cons of separate tank and all in one units? Also if there is any kind of special maintenance needed for hybrid systems. I love your channel and anything energy saving and or making our homes longer lasting.
Great content. Thank you for your work. If I may offer one suggestion, have your camera operator use a tripod.
This video was super helpful! Thank you 😊
have to say i like the bosch tankless heater it has built in flush ports
Something to think about. My Rinnai water heater (10 years old) recently developed a pinhole leak in the cold water cooper tube inside the unit, along with green mineral deposits surrounding the hole. This suggests that there has been corrosion inside the tube, and more holes are a distinct possibility. My cabin is on a well, quite hard water. When I'm gone, the water sits in the tube, and I think that over time that has resulted in the corrosion I'm seeing. I'm planning to replace the unit, but I think that in the next decade I'll plan on draining the unit when I'm away, and hope that addresses the problem.
If you dont live there a lot, put in a regular tank heater if you have the room. They're a whole lot easier to flush of minerals and build-up if you have really hard water, plus elements are $15 if they cake up with deposits.
bigpjohnson thanks for the suggestion . I’m in the mountains, winter freezing always a risk, so that’s why I went tankless.
Thank you Matt. Much appreciated!
I'm thinking dual purpose for those hot water heaters. Your description reminds me of the old radiator heaters.
Matt... Just getting thru this southern freeze and it looks as though our Rinnai R47 is leaking, near top coils - haven't taken apart, but obvious leak. Do you think the unit can be salvaged / repaired, or done for and needs to be replaced. I've had for 6 years and thanks to your video, I just learned it needed maintenance... Never done it! We've had low water pressure due to MUD district and apparently 'junk' coming in lines... So obviously several potential issues.
Matt, helpful video. But we all know this rarely, if ever, gets done unless scale becomes an issue (like clogging up shower mixing valves or spray heads)
Who installed that unit? Is that crappy quality to be expected every time? I figured they would be hardwired and have the supply lines not going at an angle across the wall. It seems like the plumber didnt really put much care into it
No, its that you're just too anal.
moncorp1 Inc Oh is that what it is? I figured if I pay a guy a grand to install something he’ll put a little pride into it. It is in fact his whole profession
As a homeowner, it would break my heart (and then send me into a rage) if this lazy, ‘hack’ installation was done on my house.
Plumbers in my area charge $300-400 to do this simple procedure. So even if you buy quality tools and pump you are saving money from day one!
Just curious but why wouldn’t you put one of those inlet screens on the hot side too so that any scale gets caught there before wreaking havoc?
The scale is from dissolved minerals. The screen wouldn't catch them.
Cisco8484 I’d agree that the scale is from dissolved minerals, but it should be formed along the wall of the boiler where that mineral rich water is flash boiling
@@Cisco8484 The scales form on the boiler and then break off after accumulating for awhile. The big chunks of minerals are what causes problems in your plumbing downstream. If it were just dissolved minerals there would be no need to descale.
I couldn't help but notice you did not service the combustion side of this unit. This should also be done every year in accordance with a flush as the burners, flame rods, and heat exchanger all get very dirty. The gas pressure should also be checked and set accordingly if possible. Rinnai has a service info sheet inside of the door of all of their units that tells you all of the specs. for setting the gas pressure. This video should just be titled how to flush your tankless water heater.
What should we bring doing for PM on the vent system.thanks
So did the heat exchanger not get flushed in this way...what was this flush then..abit confused. Ty
You did not mention that the manufacture recommends 4 gallons of 5% vinegar solution per flush. Five percent is the normal strength you will find though some discount brands may be diluted down to 3%.
Fortunately the acid content in the vinegar he used was 9%. Presumably strong enough to remove virtually all scale in the heat exchanger?
I'm a LITTLE LATE...BUT DID WATER FLOW GET BETTER DUE TO THIS METHOD..?..INFORMATIVE VIDEO THO..💪💯.!!
Excellent tutorial.
Great job Matt!
Great video. Very informative
Great video - thanks Matt
Thanks!
Helpful Tip. If you question your hardness rating and have a public water supply contact your local water utility they will be able to provide you the answer, or look at the annual Water Quality Report sometimes called the CCR - Consumer Confidence Report. They are required by the EPA to have that available to all customers and update it every year.
If your water utility gets its water from wells then the Hardness level will be higher if they get the water from a lake or any other above ground source it will be lower or “softer”
Water hardness levels are considered as following
0-75 mg/L -Soft
75-150 mg/L -Slightly Hard
150-300 mg/L - Moderately Hard
300 + mg/L -Very Hard
mg/L = milligrams per Liter other wise known as PPM or parts per million . yes in the water industry we don’t use the standard imperial measurements but if converted it would be as the following
0-1 Grains per Gallon - Soft
1-3.5 Grains - Slightly Hard
3.5 - 7 Grains - Hard
7 - 10 Grains - Moderately Hard
10 + Grains - Very Hard
Here in Central Arkansas we have some of the best Water in the United States.
The hardness of the water provided by Central Arkansas Water is between 1.0-1.7 grains/gallon or 17-29 mg/L. This is considered a “soft” water.
If you made it this far I’m impressed. I’m a licensed D-4 Water Nerd. “Keeping the water Clean and Flowing” -ME
You'd be amazed at just how many people assume that, A hot water system DOES NOT NEED ANY MAINTENANCE! Even those who build homes & remodellers. The old style-Hot water Tanks need flushed yearly if you want them to last! Or even twice per year would be best! Especially if one has hard water & an older tank style water heater.
The US has used tank heaters since forever, little maintenance was required so nobody really thought about them. With tankless, every owner needs to relearn how to deal with them. Builders and remodelers arent going to tell people their new unit/house needs *more* maintenance either.
Install a whole house water filter, it will extend the life of the heater and improve the water in general. worth the cost.
Thank you
Did you do a maintenance vid on the heat pump water heaters? If not, that'd be great 👍 thx for your great vids
If you have hard water from the city, why not release the vinegar in the system into your water lines and flush them and your faucets as well? Take off all the aerators and allow the in-line scale build up to flush from all the water lines?
If you use tankless i recommend merus ring ;) great thing.. not sure about availability in US though
I looked at your first video from 2013 and this one, and there is a conflict about the power. A few other videos say keep the power on, but you say to unplug it. Does it matter if the power is on or not? Thanks for all your videos. You have no idea how much you've helped us here in Charlotte North Carolina.
The Noritz video recommends leaving the power on. It may depend on the Mfg/Model and features/"safeties" on that unit. Check with your manufacturer.
Thanks, great video!
GREAT VIDEO !! VERY INFORMATIVE
I got a Takagi installed 14 years ago. Never flushed it yet.
My water is filtered before the softener then filtered again before the Takagi. No problems.
I still need to add those valves ..
Because I love more maintenance lol
Not sure a filter is sufficient to remove hardness, that why they use collect and flush, softeners.