My neighborhood recently had new gas feeds installed . This is the first heating season with the new service. I had to adjust the gas pressure on my two 90% units and several of my neighbors’ too. The gas utility company made absolutely no effort to inform their customers of any potential need for adjustment. I can only imagine how many more out of spec furnaces are out there. Thank you for the informative video.
Why would a utility company tell you anything? They don't service the equipment you attach. It's like asking your electric utility to repair your stove.
One KEY disclaimer here. going by the panel pressure ONLY works for Sea Level. At altitude, 3.5 would be way more gas than the air mix can burn and you would be pissing gas away out the flue. You have to go to the installation or high altitude kit instructions for the correct lower pressure. For example in Colorado at 6,800 ft you have to derrate almost 28% and use gas pressures in the 2.1-2.5 range and higher you must switch to smaller orifices. I am in the process of optimizing my furnace and going to use a combustion analyzer to find my optimum pressure and orifice size, making sure I am at the most efficient burn mix.
I also live in Colorado and was trying to understand how to set up my gas pressure properly both at the manifold and at the street level. Have you been able to figure out the heat value of the gas? The furnace manual (Carrier) requires the specific gravity of the natural gas (0.58,0.60,0.62,0.64) and the BTU/CU to find the correct pressure
@@vincenzochianese2143 Exactly. No. the local gas company was clueless. According to charts I found online, the heat value for the front range is in the 10xx range and I could not find/get the specific gravity. I purchased a combustion analyzer (arrives tomorrow) and plan to do my own measurements at #43 orifices down to 2.1 and then swap to #48 and increase pressure to see which setup gets me highest efficiency. my furnace was running at 2.55 which I think is high for 6,800 ft.. In Colorado Springs FYI.
@@OneLeggedTarantula I am in the Denver area and I believe I found the same chart you are talking about in the DOE website where yes, the values are above 1k. I believe my furnace has #44. What combustion analyzer did you buy?
You also know your gas valve is calibrated by clocking your gas meter while you adjust the input of the valve. You want to be within +/- 2% of the BTU rating of your furnace. There are caveats to adjusting this pressure ignorantly, i.e.: incomplete combustion, under-firing your heat exchanger, allowing a greater potential for condensation, over-firing your heat exchanger. All of these things are pretty serious things to consider.
I believe that operating at the lower end of the gas pressure range may cause the furnace to run slightly longer each cycle but results in more consistent and comfortable space temperature.
While setting gas pressure is very important, it should also be noted that changing gas pressure will change your combustion properties. Such as allowing too much CO, having too hot of a temp stack. This requires a combustion analyzer. This is still an excellent video for the topic.
No not when it's specified lowest setting in your units spec plate. He is not suggesting going below the lowest pressure recommended by the manufacturer.
Thanks. Worth mentioning, you said that to test the pressure for high flame on a two stage furnace, turn up the thermostat. True, but only if you have the two stage thermostat. Many installers save a few bucks by putting in a much cheaper one stage stat, and wiring it (W1 - W2 strap) so that the internal timer in the furnace finally asks for high flame after a preset number of minutes, and only if there is still a call for heat, if the target has not yet been reached. If you want to force high flame on demand, you remove the strap, start the furnace, and then when you reinstall the W1-W2 strap, high flame will start. BTW, like many owners with singlestage stats in mild climates, I made it a one stage by exchanging the strap for a simple switch, which instantly makes it a two stage only when operated for need. That is because with the strap in, the timer will invoke high flame moments before the target is met, briefly making a lot of fan noise and being inefficient.
Sad to hear that some installers cheapen out by installing a one-stage thermostat on a two-stage system. Nowadays, two-stage thermostat costs nothing more than one-stage. And many utility companies sell high quality smart thermostats for as little a dollar after rebate, or even provide for free if customer enrolls in energy saving program.
If you decide to do this, then please find the service manual for your furnace and read it carefully. This video shows you the core things that you’ll need to know on any furnace, but there are models out there that have quirks (multi stage furnaces in particular) and the procedure is slightly different. So please read the manual.
Man its bad enough I see ICP furnaces not vented properly in the field, but now here is one on you tube. The furnace came with a rubber coupling and two hose clamps. it is to be installed at the outlet of the cabinet. A short piece is cut usually 10 to 10-1/8 varies a bit so need to measure from the inducer to the plastic outlet ring. it is glued into the outlet ring, once the glue is set up it is installed between the inducer and the cabinet. then the rubber collar is installed and clamped to the ring. From there the field side of the vent is ran clamping it to the coupling. This allows for easier service in the future. Thats how you piss a tech of on a friday afternoon when he has to replace the inducer and the flue separation kit wasn't used, he doesn't have a coupling to just cut the vent, so now he has a PITA replacement, as the inducer assembly can still be replaced, but its a battle. Installers keep your techs happy, install the flue as per manufactures design. Also a tee with a drain line or a drip leg must be installed on the intake. ICP will not warranty the gas valve if it fails due to moisture from the intake.
Thank you for this video and giving us knowledge that we didnt have yesterday. I appreciate the time you take to show us how things work and give us the respect to know that if we're not comfortable we dont touch this stuff but if we are then we have the knowledge to understand it... Please dont listen to these morons on here that hate learning... Thank you!
So if you reduce the pressure ultimately reducing the burner flame, how much longer is the furnace run time to satisfy the thermostat request and heat the house?
So too many inches of gas on low means two stage condensing furnace does not operate at peak efficiency. Right amount of pressure means more heating to the air with less gas and electrical consumption. Same on high speed on two stage furnace , although then you know that efficiency drops as heating rate is increased@@diyhvacguy
@@diyhvacguy it runs longer and drops the air oputlet temperature.. money savings is only really noticed at all on a 90+ furnace where you are dropping the secondary heat exchanger temperature allowing more condensation to occur.. on modern furnaces with ECM inducers. ()namely modulating the 2 stage) the inducer will reduce it's speed in response to a lowered gas valve setting.. those furnaces continually test for the lowest inducer speed that will still trigger the pressure switch for the exhaust.. I have the second stage on my 2 stage trane unit dropped about 20% over label.. i still get good quick crossover but much more codnensation and longer run time which allows the firnace to run in its most efficient state.. dropping gas pressure on an 80% unit really doesnt do alot as the inducer spoeed stays on full which tends to run way more air than necessary for good combustion.. you can see it when running a combustion analysis on the exhaust. (testo 320)..
@@joemartinez-673 set too high you are likely to incur an initial rollout on startup which will trip the rollout limit.. possibly disrupt the draft flow and trip out the pressure switch. on a 90+ if it continues to run, youl;l hit the stack temp limit which is typically only 150-160f. and it will shut down.. on an 80% if you set it high enough to damage the heat exchanger it will shut down on high limit prior... if the blower speed is set high enough the unit will run with no other ill ewffects than warmer air and short cycling.
Thanks for the meter recommendations. I settled on the better of the two, cheap meters just don't last. Trust me! Plus they have very limited features. Hopefully you made a little cash from my purchase since I tried using your link in the Amazon store. Thanks for all the great content. I think you're going to end up saving me some cash down the road. Plus I'd feel more comfortable working on it myself vs having somebody else touch it and screw it up. And my buddy at work lets me use his $600 fluke meter, so I'm going to let him use my new manometer to check his furnace. Maybe I'll help him. World Peace!
I bought a manometer and checked the pressure and it was less than the furnace manual called for. The installer never checked it . I think I’ll stick with the manual prescribed pressure (at our 35 feet above sea level).
I forgot to say that I have a two stage furnace and two stage gas valve . The stage 1 gas pressure is set at 1.8 psi for mine and that’s where it runs most of the time for temp. maintenance. I suppose that’s partly why you get better efficiency.
I was going through two tanks of propane a year. Gas valve went out. I bought a cheapo manometer and replaced the gas valve. Now im just getting my first tank fill of the year. Wish i knew how far out my old valve was before i replaced it! Im thinking it was pretty inefficient
Lowering the gas pressure does not save fuel! Underfiring the furnace changes the fuel to air mix and actually slightly reduces efficiency. What matters for energy use is efficiency. The reason some manufacturers give a range is to adjust for btu content and density of the fuel. IT IS NOT so you can set it to whatever you want. If the orifices in the furnace are for 1000 btu per cu ft and you have 1050 in your area as an example, the pressure needs to be slightly lower than the standard 3.5 on hi, 1.5 to 1.7 on low. This is all detailed in the install manuals no one seems to read. The btu input needs to be what is on the rating plate for both low and high fire. Only reduce btu input if required for de-rating! If the temp rise is too high, raise the fan speed, don't cut the gas pressure!
As an HVAC pro, what do you recommend for a good smart thermostat? I want one we can connect to our phones but unfortunately our house has 3 different thermostats… I good and a lot of bad things about Nest plus I don’t really wanna drop $600! Thanks
So currently, the manometer costs $164. Assuming my furnace is running within spec but on the high side, how long would it take to recover that $164? Alternatively, I can get my furnace checked and "tuned" by a professional for under $100. That makes more sense unless that tuning has to be repeated every year.
The manometer I have in the description is like $30. The fieldpiece I highly recommend for people in this trade but otherwise homeowners could totally get the cheap one which works just as well it just doesn’t have some of the features.
@@not_listening2792 Water column manometer is actually more reliable than electronic manometer because it can't get out of calibration. However, the $30 manometer is reliable as long as it's not abused.
Great video --- I've read that (going too low) on gas pressure can cause incomplete burning of the gas and cause an increase in harmful gases inside the furnace that could get into the home and (going too high) on gas pressure besides increasing noise also makes the flames hotter and it can damage components like the regulator and manifold orifices, etc., over time, i've also read that running too hot from too much pressure can also overheat and damage the blower motor. ---------- Is that true and I wish you would have used a temperature gun (IR Gun?) so we could see the flame temps change as you increased and decreased the gas pressure.
@@Bowhunters6go8xz6x If the blower compartment is hot enough to melt the windings then the entire unit must be on fire. The blower is in the unheated return air path so it stays cool whenever it is running. And the high limit overload will shut down the burners if the furnace reaches dangerous temperatures. Most furnaces are updraft so the blower is below the heat exchanger. If you have a downdraft furnace (common in mobile homes) the motor will be above the heat exchanger and I suppose it will get quite hot (due to the hot air naturally rising) if the motor stops running for whatever reason. It possibly could get hot enough to damage the insulation but the copper itself won't melt.
@@eDoc2020 --- Its not going to melt the windings overnight but over time (one article I read said) 130c/266F for 5,000 or more hours can ruin a furnace blower motor and some blower motors are more cheaply built than others. The guy that does this channel has mentioned that it can happen if the furnace runs hot all the time but it does take time. Not going to argue about it.
@@Bowhunters6go8xz6x I agree the windings will get damaged by elevated temperatures over time. My point was it's the enameled insulation which will fail and make the windings short out. The copper itself won't melt.
Another great and very useful video. I've purchased test 310 II on Amazon. Can you recomend using it for this adjustment of Fieldpiece SDMN5 is better?
I know it will vary greatly, depending on the situation, but how much savings are we talking about for a typical winter in Michigan? Enough to at least pay for price of the manometer?
Good point. I assume over time you would recoup the cost of the meter so long as the meter doesn't crap out and you check & adjust it every year. I'm not an HVAC technician but rather a GM technician for 36 years. For someone only using the meter once or twice a year, I would recommend removing the batteries after you're done using it so they don't leak and ruin the meter.
@@ryanbrown5334 can you please elaborate on how this would make it less efficient by adjusting it to factory specifications? I'm always looking to learn, especially from someone who is a good teacher and explains things well.
under-firing a furnace by cutting the pressure means the burners are getting too much oxygen. slightly reduces combustion efficiency. The btu input into the furnace should be what is stated on the nameplate. @@kevn33
My Furnace stamp shows 3.5 in Wc. Does this mean there is no range available to adjust. Does my furnace have to be set at only 3.5 to operate properly. Thanks. Love your channel
I was going to do this but the information to adjust manifold pressure isn't listed on or anywhere inside my furnace and I couldn't find it on the internet either.
Do you have any tricks of the trade to loosen up the port where you insert the fitting to manometer? Mines stuck. Almost looks like it might have Loctite on it. Ugh. 😮
it depends on the size of the furnace and the size of the home and ofc your location. For example here in Texas most furnaces are oversized because of higher cooling loads. My house has a 80k 80% BTU furnace but manual J would only call for ~30k BTU total. That being said my gas furnace is about 2x bigger than needed because I need a bigger airhandler during the summer. In my case, dialing it back saves me money and improves comfort too... YMMV
Great video but I have one question if you lower the gas pressure to the lowest setting does that lower the btu(heat) output of the furnace? If lowering the gas pressure, does decrease the furnace heat(btu) output then the furnace has to run longer which will increase the repair costs much higher overtime due to the extended run times. The temperature in the house will feel colder until the thermostat temperature set point is reached. If the btu's are lower this should extend the life of the heat exchanger.
My friend has a 2005 miller M1M in a mobile home. Will adjusting this really save enough to justify even just the $37 for the Manometer? It is a very loud unit but that is more attributed to the blower.
My manifold pressure is a single number 3.5, not a range...what is the assumption 3.2-3.8? Older 84% efficiency Rheem Criteon 2 furnace that sounds like jet airplane, very loud.
i have mini gree aircondition system in the caribbean i will like to know if they come with the with a built protection to reduce the power when the system comes on ,i ask the tech guy there but he,s not sure if not could i install the icm 80 on my systems
The brass screw cap for pressure was screwed on so tight it's stuck. It started to strip while attempting to remove. Any recommendations for safely removing?
❤I love watching your channel. With a manometer, where can I get or buy or order the clear vinyl tube with an attenuated tip. How do I look for it? Looking forward to your reply. Thanks!
It is the BTU of the furnace vs the volume air blowing through the heat exchanger "plenum", cooling it below the "fan run" limit switch, which tells the blower that the plenum is now at correct temperature. Setting pressure too high will trip the "overheat" limit switch. The blower should not turn on and off repeatedly during the call for heat from the thermostat.
I've a couple of questions. First, how much does this tend to stray? In other words, does it need to be checked annually? Second, if I paid the Xcel Energy guy to to a "tune up" on my furnace, is this something he would have likely done? Tried looking on the Xcel website for an answer to that 2nd one, but...
Optimal setting for gas pressure value changes only when the BTUs per cu.ft. of gas changes very much. If you look at your gas bill, you'll probably find that it barely changes from month to month, not enough to make it worth adjusting the valves. If the BTU's per cu. ft. actually changed very often, then the federal gov't would mandate O2 sensors in furnaces and automatic adjustment of fuel/air mixture, like in automobiles.
Decent furnace tech would check combustion with meter (and preferably give customer a printout of results). Would also check heat rise on both high and low fire. Would also check static pressure of entire furnace and of just the evaporator (if system has A/C) to determine if evaporator is reducing airflow enough to need cleaning.
But aren't you getting less heat at the same time? Won't your furnace have to run longer to do the same job? In the long run will you be using the same amount of gas? So many questions.
This was exactly my question. By using less gas, you are producing less heat, therefore necessitating a longer runtime. Now, if the furnace is less efficient at the higher pressure settings, then it might make sense to turn it down.
@@MrFescue it also depends on location... here in Texas most furnaces are oversized because of higher cooling load thus the need of a bigger air handler. My home has a 2x bigger furnace than necessary so dialing it back definitely saves money. YMMV, up north you likely won't see much if any benefit of doing this.
You make good videos but your clickbait titles are just making you seem disingenuous or not reputable. Just name the video what your actually teaching..
My neighborhood recently had new gas feeds installed . This is the first heating season with the new service. I had to adjust the gas pressure on my two 90% units and several of my neighbors’ too. The gas utility company made absolutely no effort to inform their customers of any potential need for adjustment. I can only imagine how many more out of spec furnaces are out there.
Thank you for the informative video.
Why would a utility company tell you anything? They don't service the equipment you attach. It's like asking your electric utility to repair your stove.
One KEY disclaimer here. going by the panel pressure ONLY works for Sea Level.
At altitude, 3.5 would be way more gas than the air mix can burn and you would be pissing gas away out the flue.
You have to go to the installation or high altitude kit instructions for the correct lower pressure.
For example in Colorado at 6,800 ft you have to derrate almost 28% and use gas pressures in the 2.1-2.5 range and higher you must switch to smaller orifices.
I am in the process of optimizing my furnace and going to use a combustion analyzer to find my optimum pressure and orifice size, making sure I am at the most efficient burn mix.
I also live in Colorado and was trying to understand how to set up my gas pressure properly both at the manifold and at the street level. Have you been able to figure out the heat value of the gas? The furnace manual (Carrier) requires the specific gravity of the natural gas (0.58,0.60,0.62,0.64) and the BTU/CU to find the correct pressure
@@vincenzochianese2143 Exactly. No. the local gas company was clueless. According to charts I found online, the heat value for the front range is in the 10xx range and I could not find/get the specific gravity. I purchased a combustion analyzer (arrives tomorrow) and plan to do my own measurements at #43 orifices down to 2.1 and then swap to #48 and increase pressure to see which setup gets me highest efficiency. my furnace was running at 2.55 which I think is high for 6,800 ft.. In Colorado Springs FYI.
@@vincenzochianese2143 www.eia.gov/dnav/ng/hist/nga_epg0_vgth_sco_btucfa.htm
@@OneLeggedTarantula I am in the Denver area and I believe I found the same chart you are talking about in the DOE website where yes, the values are above 1k.
I believe my furnace has #44. What combustion analyzer did you buy?
Sea level to 4500 Ft. A lot of people live in that range. Really a pain for folk living above 4000 Ft.
You also know your gas valve is calibrated by clocking your gas meter while you adjust the input of the valve. You want to be within +/- 2% of the BTU rating of your furnace.
There are caveats to adjusting this pressure ignorantly, i.e.: incomplete combustion, under-firing your heat exchanger, allowing a greater potential for condensation, over-firing your heat exchanger. All of these things are pretty serious things to consider.
Just the video I need. Simple and clear. I was just afraid to touch the valve fear of messing it up😊
I believe that operating at the lower end of the gas pressure range may cause the furnace to run slightly longer each cycle but results in more consistent and comfortable space temperature.
While setting gas pressure is very important, it should also be noted that changing gas pressure will change your combustion properties. Such as allowing too much CO, having too hot of a temp stack. This requires a combustion analyzer. This is still an excellent video for the topic.
Thank you this is crazy I can’t believe this shits on UA-cam
No not when it's specified lowest setting in your units spec plate. He is not suggesting going below the lowest pressure recommended by the manufacturer.
Thanks. Worth mentioning, you said that to test the pressure for high flame on a two stage furnace, turn up the thermostat. True, but only if you have the two stage thermostat. Many installers save a few bucks by putting in a much cheaper one stage stat, and wiring it (W1 - W2 strap) so that the internal timer in the furnace finally asks for high flame after a preset number of minutes, and only if there is still a call for heat, if the target has not yet been reached. If you want to force high flame on demand, you remove the strap, start the furnace, and then when you reinstall the W1-W2 strap, high flame will start. BTW, like many owners with singlestage stats in mild climates, I made it a one stage by exchanging the strap for a simple switch, which instantly makes it a two stage only when operated for need. That is because with the strap in, the timer will invoke high flame moments before the target is met, briefly making a lot of fan noise and being inefficient.
Sad to hear that some installers cheapen out by installing a one-stage thermostat on a two-stage system. Nowadays, two-stage thermostat costs nothing more than one-stage. And many utility companies sell high quality smart thermostats for as little a dollar after rebate, or even provide for free if customer enrolls in energy saving program.
If you decide to do this, then please find the service manual for your furnace and read it carefully. This video shows you the core things that you’ll need to know on any furnace, but there are models out there that have quirks (multi stage furnaces in particular) and the procedure is slightly different. So please read the manual.
Much love. This is priceless knowledge if you’re inclined. But most are not.
Please do a similar video for a two stage furnace. Thanks bud
Man its bad enough I see ICP furnaces not vented properly in the field, but now here is one on you tube. The furnace came with a rubber coupling and two hose clamps. it is to be installed at the outlet of the cabinet. A short piece is cut usually 10 to 10-1/8 varies a bit so need to measure from the inducer to the plastic outlet ring. it is glued into the outlet ring, once the glue is set up it is installed between the inducer and the cabinet. then the rubber collar is installed and clamped to the ring. From there the field side of the vent is ran clamping it to the coupling. This allows for easier service in the future.
Thats how you piss a tech of on a friday afternoon when he has to replace the inducer and the flue separation kit wasn't used, he doesn't have a coupling to just cut the vent, so now he has a PITA replacement, as the inducer assembly can still be replaced, but its a battle. Installers keep your techs happy, install the flue as per manufactures design.
Also a tee with a drain line or a drip leg must be installed on the intake. ICP will not warranty the gas valve if it fails due to moisture from the intake.
Another Banger Of A Video 📹 From An Incredible Guy. I Wish You The Best Brother.
Thanks bro 👊🏼
Thank you for this video and giving us knowledge that we didnt have yesterday. I appreciate the time you take to show us how things work and give us the respect to know that if we're not comfortable we dont touch this stuff but if we are then we have the knowledge to understand it... Please dont listen to these morons on here that hate learning... Thank you!
Thank you for this video and giving us knowledge that we didnt have yesterday.
thank you for sharing! I have an older manometer I think it should work.
Very educational, panel adjustment numbers for water column just like that , awesome video
So if you reduce the pressure ultimately reducing the burner flame, how much longer is the furnace run time to satisfy the thermostat request and heat the house?
Very minimally longer runtime
So too many inches of gas on low means two stage condensing furnace does not operate at peak efficiency. Right amount of pressure means more heating to the air with less gas and electrical consumption. Same on high speed on two stage furnace , although then you know that efficiency drops as heating rate is increased@@diyhvacguy
@@diyhvacguy it runs longer and drops the air oputlet temperature.. money savings is only really noticed at all on a 90+ furnace where you are dropping the secondary heat exchanger temperature allowing more condensation to occur.. on modern furnaces with ECM inducers. ()namely modulating the 2 stage) the inducer will reduce it's speed in response to a lowered gas valve setting.. those furnaces continually test for the lowest inducer speed that will still trigger the pressure switch for the exhaust.. I have the second stage on my 2 stage trane unit dropped about 20% over label.. i still get good quick crossover but much more codnensation and longer run time which allows the firnace to run in its most efficient state.. dropping gas pressure on an 80% unit really doesnt do alot as the inducer spoeed stays on full which tends to run way more air than necessary for good combustion.. you can see it when running a combustion analysis on the exhaust. (testo 320)..
You failed to talk about " over fire," what happens to the heat exchanger!
@@joemartinez-673 set too high you are likely to incur an initial rollout on startup which will trip the rollout limit.. possibly disrupt the draft flow and trip out the pressure switch. on a 90+ if it continues to run, youl;l hit the stack temp limit which is typically only 150-160f. and it will shut down.. on an 80% if you set it high enough to damage the heat exchanger it will shut down on high limit prior... if the blower speed is set high enough the unit will run with no other ill ewffects than warmer air and short cycling.
Thank you papa God bless you and your family
Thanks for the meter recommendations. I settled on the better of the two, cheap meters just don't last. Trust me! Plus they have very limited features. Hopefully you made a little cash from my purchase since I tried using your link in the Amazon store. Thanks for all the great content. I think you're going to end up saving me some cash down the road. Plus I'd feel more comfortable working on it myself vs having somebody else touch it and screw it up. And my buddy at work lets me use his $600 fluke meter, so I'm going to let him use my new manometer to check his furnace. Maybe I'll help him. World Peace!
Awesome! Thanks so much for the support. Cheers
I bought a manometer and checked the pressure and it was less than the furnace manual called for. The installer never checked it . I think I’ll stick with the manual prescribed pressure (at our 35 feet above sea level).
I forgot to say that I have a two stage furnace and two stage gas valve . The stage 1 gas pressure is set at 1.8 psi for mine and that’s where it runs most of the time for temp. maintenance. I suppose that’s partly why you get better efficiency.
2-stage does not save fuel, it is for comfort. burns less gas over a longer period of time.@@rzh3443
I was going through two tanks of propane a year. Gas valve went out. I bought a cheapo manometer and replaced the gas valve. Now im just getting my first tank fill of the year. Wish i knew how far out my old valve was before i replaced it! Im thinking it was pretty inefficient
Lowering the gas pressure does not save fuel! Underfiring the furnace changes the fuel to air mix and actually slightly reduces efficiency. What matters for energy use is efficiency.
The reason some manufacturers give a range is to adjust for btu content and density of the fuel.
IT IS NOT so you can set it to whatever you want.
If the orifices in the furnace are for 1000 btu per cu ft and you have 1050 in your area as an example, the pressure needs to be slightly lower than the standard 3.5 on hi, 1.5 to 1.7 on low.
This is all detailed in the install manuals no one seems to read.
The btu input needs to be what is on the rating plate for both low and high fire.
Only reduce btu input if required for de-rating!
If the temp rise is too high, raise the fan speed, don't cut the gas pressure!
Very good teaching video!
I like the knowledge, thank you. However, I won't most installers set this up correctly when they put in the unit?
You’d be surprised man. A lot of people don’t check it at the time of installation.
I’ve been in the industry for 16 years. Proper commissioning of residential equipment on new installation is rarely done. If done, not properly.
As an HVAC pro, what do you recommend for a good smart thermostat? I want one we can connect to our phones but unfortunately our house has 3 different thermostats… I good and a lot of bad things about Nest plus I don’t really wanna drop $600! Thanks
So currently, the manometer costs $164. Assuming my furnace is running within spec but on the high side, how long would it take to recover that $164? Alternatively, I can get my furnace checked and "tuned" by a professional for under $100. That makes more sense unless that tuning has to be repeated every year.
The manometer I have in the description is like $30. The fieldpiece I highly recommend for people in this trade but otherwise homeowners could totally get the cheap one which works just as well it just doesn’t have some of the features.
@@diyhvacguy Couldn't you use a water column manometer?
@@not_listening2792 Water column manometer is actually more reliable than electronic manometer because it can't get out of calibration. However, the $30 manometer is reliable as long as it's not abused.
You can make your own "U-tube" water manometer out of clear tubing and water. Instructions on You Tube.
Will a sphygmomanometer work? Asking for Zach Sherwin
Interesting video. But if one had to buy the manometer to do this… you wont save enough in 5 years to pay 200 bucks for the monometer….
The other manometer I have listed is like 30 bucks. So that’s an option :) some people just look for excuses to buy cool tools haha
Great video --- I've read that (going too low) on gas pressure can cause incomplete burning of the gas and cause an increase in harmful gases inside the furnace that could get into the home and (going too high) on gas pressure besides increasing noise also makes the flames hotter and it can damage components like the regulator and manifold orifices, etc., over time, i've also read that running too hot from too much pressure can also overheat and damage the blower motor. ---------- Is that true and I wish you would have used a temperature gun (IR Gun?) so we could see the flame temps change as you increased and decreased the gas pressure.
Running too hot won't hurt the blower motor, however it can damage the heat exchanger.
@@eDoc2020 I've heard it said that it can melt copper windings inside the blower motor !
@@Bowhunters6go8xz6x If the blower compartment is hot enough to melt the windings then the entire unit must be on fire. The blower is in the unheated return air path so it stays cool whenever it is running. And the high limit overload will shut down the burners if the furnace reaches dangerous temperatures. Most furnaces are updraft so the blower is below the heat exchanger. If you have a downdraft furnace (common in mobile homes) the motor will be above the heat exchanger and I suppose it will get quite hot (due to the hot air naturally rising) if the motor stops running for whatever reason. It possibly could get hot enough to damage the insulation but the copper itself won't melt.
@@eDoc2020 --- Its not going to melt the windings overnight but over time (one article I read said) 130c/266F for 5,000 or more hours can ruin a furnace blower motor and some blower motors are more cheaply built than others. The guy that does this channel has mentioned that it can happen if the furnace runs hot all the time but it does take time. Not going to argue about it.
@@Bowhunters6go8xz6x I agree the windings will get damaged by elevated temperatures over time. My point was it's the enameled insulation which will fail and make the windings short out. The copper itself won't melt.
Another great and very useful video. I've purchased test 310 II on Amazon. Can you recomend using it for this adjustment of Fieldpiece SDMN5 is better?
Said clearly 1.5” w.c on gas vale
I know it will vary greatly, depending on the situation, but how much savings are we talking about for a typical winter in Michigan? Enough to at least pay for price of the manometer?
Good point. I assume over time you would recoup the cost of the meter so long as the meter doesn't crap out and you check & adjust it every year. I'm not an HVAC technician but rather a GM technician for 36 years. For someone only using the meter once or twice a year, I would recommend removing the batteries after you're done using it so they don't leak and ruin the meter.
Oh I’m sure. And you don’t have to check this every year. Once it’s set it’s set. You could check it every few years if you wanted to.
Lowering gas pressure reduces efficiency
@@ryanbrown5334 can you please elaborate on how this would make it less efficient by adjusting it to factory specifications? I'm always looking to learn, especially from someone who is a good teacher and explains things well.
under-firing a furnace by cutting the pressure means the burners are getting too much oxygen. slightly reduces combustion efficiency.
The btu input into the furnace should be what is stated on the nameplate.
@@kevn33
You failed to talk about " over firings " . What happens to the heat exchanger. Cracked heat exchanger.
What are some symptoms the gas furnace does to indicate the gas needs to be adjusted?
My Furnace stamp shows 3.5 in Wc. Does this mean there is no range available to adjust. Does my furnace have to be set at only 3.5 to operate properly. Thanks. Love your channel
I was going to do this but the information to adjust manifold pressure isn't listed on or anywhere inside my furnace and I couldn't find it on the internet either.
Awesome!!! Great tip!!
Great video! Could you provide a link for the monometer you used? I checked your store and couldn’t find it.
You can find it under furnace replacement items. I’ll leave them in the description as well. Cheers
Do you have any tricks of the trade to loosen up the port where you insert the fitting to manometer? Mines stuck. Almost looks like it might have Loctite on it. Ugh. 😮
Does this concept apply to gas boilers?
Lowering the pressure will just make it run longer to satisfy the thermostat correct?
Very minimal
@@diyhvacguy great thank you!
it depends on the size of the furnace and the size of the home and ofc your location. For example here in Texas most furnaces are oversized because of higher cooling loads. My house has a 80k 80% BTU furnace but manual J would only call for ~30k BTU total. That being said my gas furnace is about 2x bigger than needed because I need a bigger airhandler during the summer. In my case, dialing it back saves me money and improves comfort too... YMMV
Excellent
Is this adjustment not normally done by the installation tech?
You’d be surprised
Maybe if he doesn't have a hangover. Even then, it's hit or miss.
Great video but I have one question if you lower the gas pressure to the lowest setting does that lower the btu(heat) output of the furnace? If lowering the gas pressure, does decrease the furnace heat(btu) output then the furnace has to run longer which will increase the repair costs much higher overtime due to the extended run times. The temperature in the house will feel colder until the thermostat temperature set point is reached. If the btu's are lower this should extend the life of the heat exchanger.
Yes, changing the gas pressure affects the heat output.
My friend has a 2005 miller M1M in a mobile home. Will adjusting this really save enough to justify even just the $37 for the Manometer? It is a very loud unit but that is more attributed to the blower.
My manifold pressure is a single number 3.5, not a range...what is the assumption 3.2-3.8? Older 84% efficiency Rheem Criteon 2 furnace that sounds like jet airplane, very loud.
I was wondering the same thing.
i have mini gree aircondition system in the caribbean i will like to know if they come with the with a built protection to reduce the power when the system comes on ,i ask the tech guy there but he,s not sure if not could i install the icm 80 on my systems
What happens if i just turn down the gas by throttling the gas valve and here the furnace flames getting smaller/quieter
You could risk being out of that range and have incomplete combustion. But that’s the point of the range on the back of the cover panel
I have a gas pressure gage how would I convert psi to inches of wc thanks
The brass screw cap for pressure was screwed on so tight it's stuck. It started to strip while attempting to remove. Any recommendations for safely removing?
Drill it out and get a replacement. It’s soft metal
❤I love watching your channel. With a manometer, where can I get or buy or order the clear vinyl tube with an attenuated tip. How do I look for it?
Looking forward to your reply.
Thanks!
Just look up gas pressure adapter hose 👍🏼
If the range is 1.4 - 1.8 why wouldn't you use the lower pressure to save fuel?
It is the BTU of the furnace vs the volume air blowing through the heat exchanger "plenum", cooling it below the "fan run" limit switch, which tells the blower that the plenum is now at correct temperature. Setting pressure too high will trip the "overheat" limit switch. The blower should not turn on and off repeatedly during the call for heat from the thermostat.
@@victorsteerup4582 Modern furnaces don't use limit switches to activate the fan during normal operation. They usually just use timers.
I've a couple of questions. First, how much does this tend to stray? In other words, does it need to be checked annually? Second, if I paid the Xcel Energy guy to to a "tune up" on my furnace, is this something he would have likely done? Tried looking on the Xcel website for an answer to that 2nd one, but...
Optimal setting for gas pressure value changes only when the BTUs per cu.ft. of gas changes very much. If you look at your gas bill, you'll probably find that it barely changes from month to month, not enough to make it worth adjusting the valves. If the BTU's per cu. ft. actually changed very often, then the federal gov't would mandate O2 sensors in furnaces and automatic adjustment of fuel/air mixture, like in automobiles.
Decent furnace tech would check combustion with meter (and preferably give customer a printout of results). Would also check heat rise on both high and low fire. Would also check static pressure of entire furnace and of just the evaporator (if system has A/C) to determine if evaporator is reducing airflow enough to need cleaning.
How does this save money?
By using less gas
But aren't you getting less heat at the same time? Won't your furnace have to run longer to do the same job? In the long run will you be using the same amount of gas? So many questions.
This was exactly my question. By using less gas, you are producing less heat, therefore necessitating a longer runtime. Now, if the furnace is less efficient at the higher pressure settings, then it might make sense to turn it down.
@@diyhvacguy It will use the same amount as burner will have to stay on longer. Are you a troll or just doing as a clickbait lure.
@@MrFescue it also depends on location... here in Texas most furnaces are oversized because of higher cooling load thus the need of a bigger air handler. My home has a 2x bigger furnace than necessary so dialing it back definitely saves money. YMMV, up north you likely won't see much if any benefit of doing this.
My gas pressure keeps changing from 1.7 to 3.8. And the flame flutters. Does anyone have similar issues ?
This guy is nuts……..
You can restrict the gas flow by chewing bubble gum then cramming it up on one of the orifices
You make good videos but your clickbait titles are just making you seem disingenuous or not reputable. Just name the video what your actually teaching..