How to adjust airflow and make hvac magic?
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- Опубліковано 10 тра 2023
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That duct system is nice! I’ve never been a fan of York but you how the whole brand thing goes. Great work again bro.
You don't adjust airflow to delta T to be 20 degree, you adjust airflow to system manufacturer's requirements, (you design your ducts to that requirements). If everything is done correctly usually you will get delta T of 20 deg or slightly higher. If ducts are done correctly they are not noisy. It is like trying to meet fuel economy standards by driving your car no more then 25 mph. Thanks for posting your video!
Thank You !!! system airflow chart and Man J not Delta T !!!
I wish we had basement/crawl spaces for ducts to go here in Texas. So much cooling lost with ducts in the attic.
Those Accurite thermometer/hygrometers are okay but you need to test the accuracy of the humidity with a salt test as they are usually off. Get a small container (maybe 2 ounces) and fill it with a damp paste of table salt (not super saturated). Put that in a zip lock freezer bag along with the Accurite and leave it in a room around 70 - 72 degrees for 24 hours. The humidity should be 75%. If not, just mark the device how many points its off either way and you'll have an accurate unit. (The temps are usually all good on these). I have over 15 of these with most of them in coolers used as cigar humidors with several placed around the house and the outdoor shed.
Excellent...you did a great job....I never ever had an a/c tech do what you did....never ever once was the subcool or superheat checked or balancing the the air flow.
Thanks 👍
Good stuff as always from the hvac boss
Don't own a house, but I am excited about hvac! Great job, will remember the 20 degrees differentiation and that variable fans can run too fast and loud.
Awesome i'm glad you learn something my friend
But they slow to a whisper to maintain temp. I got one.
Nice looking job!!!! Getting that evapor coil as cold as possible slowing dowing the fan speed, Question what was the total static pressure on the duct system? looked good no vent ducts on the end looked well balanced, keep up the great work bro 👏
Check the static pressure bro! This will simplify your process! .5-.7 on most models. Then go level the vents. Nice video.
thanks 👍 😊
Great video Taddy !! Wish I could find someone like you. Thanks 👍🏽👍🏽
You're welcome thank you so much for watching
I feel so antiquated with my 2004 Trane Heat Pump....everything is so fancy now
They don’t last no more than 15 years lol
I do lots of auto ac repairs, replaced an evaporator in my truck recently, thinking of doing this as a job :lol: It is similar. There is no subcool on a truck though :lol:. Once the truck moves everything changes. It is charged strictly by weight.
Most techs or installers don't do this. Also true Delta t requires humidity reading. The higher the humidity the less the split will be. So you might b be at 17° split then when humidty drops it might read 20°. Good work like watching you.
you are right, most Real Techs actually do it right, lol
In college (mid '80s) I got fed up with our apartment's system always blowing like a hurricane. Who thought that made sense? I took off the cover and discovered the fan had 3 speeds, adjustable by putting the wire on a different terminal. Went from max to min, the place was far quieter and cooled at least as well.
Today I'm wondering if my upstairs air handler has a similar secret to tell.
Thank you for the tip you are the best
I got a similar york unit. Its capable of dehumming also.
So far like the unit.
Not a fan of the flex in my attic though. I am foamed in the attic.
I hate hearing the vents also. Had a tech come by and want to turn up the fans.
Need more like you.
All air conditioning dehumidifies. Some better than others
@@racegrubb2152 yes a product of creating cold air. However some have a specific mode to dehum.
Beautiful job, I hate it when the returns are sucking hard, and the vents are roaring. Man! that looks nice.
Thank you brother
Careful with those cheap temp/hygrometer. I have 3 of them that all read wildly different values sitting next to each other. I have checked their calibration and 1 of 3 was with 3% RH at 50%, others were 7 and 8% off.
Looks nice on a, from what I can tell, a fairly new house and duct system. What about a 30-year-old one?
Your all video knowledgebel nice sir
Great video, unfortunately, from house owning experience, not all duct system is done well. Current house on a dual zone system, and struggled for a year to get it better, and it will never be correct, unless I want to rip apart a finished basement and fix all the ducting. But I have learned a ton the last 4 years becaue of this house
I had same problem when I moved into my new mobile home. The system was not commissioned. Installers left fan setting on highest setting and I had great delta T but humidity was off the chart. Very uncomfortable. Changed fan settings to lowest speed and now it’s very comfortable.
Glad to hear my friend
If I only had a dollar for every time I had to adjust air handler fan from it's absolute maximum cfm { usually the factory setting} down to the cfm that matches the size of condensing unit. Well, I guess you could say I've earned thousands of dollars doing exactly that.
You're the man
Good job!
Hi Taddy,
Love watching your videos! You are very thorough with your work. I have a question regarding air flow. I noticed the return in my second floor is not pulling any air in. When I block the return in the first floor the upstairs return then starts pulling air in. Do you have any ideas on what the issue(s) could be?
I just found a new favorite hvac channel 👍🏽
Excellent
Well factory charge is 15ft on that York. Then there is a chart to add after that. Off top of my head its .6 oz per ft after. I would add extra charge befprw opening valves. Dip switches should have been set before turning on power. Rwmember long flex lines past 5' add static and drop cfm/pascal. When in doubt pipe it out. Flex should ONLY be use to minimize vibration.
As a side bonus humidity will be much better controlled.
Well done
Thank you
You may have lower temperature now but are not providing enough airflow to properly cool the space. Adjust the fan speed can cause higher electricity also. I’m more concerned that unit may not be the proper tonnage for the space.
This is a foam insulated house 🏠
Works great 👍
Nice good job
Daddy is the man!
1st video I’ve watched if your an internet definitely subscribed now! Good information man. Wish all Hvac techs had the same passion to make things best as possible. Bought new home couple years ago and it has good trane and Honeywell equipment but install and set up was awful! This helped
Thanks for the sub!
actually appears to be doing Start Up of a New Install. most Real Techs don't hack at it, they actaully check the blower speed chart and make adjustments without doing a you Tube video so you never see what we do.,
@@craigkennedy9968 that’s good to hear . I’m just stating in my case it was less than ideal or average . The company was t.a. Kaiser and they were definitely sub par . There wasn’t much I could do at the time . I do industrial hvac , work through a union so I have some higher expectations I suppose but if you seen the install brother you would be ashamed for them . I respect the good ones . Appreciate the feedback
I just had my 5 ton American standard 2002 serviced by my cousin. I called an air conditioning company who informed me that I have R 22. Which is so expensive at $275 a pound, i might be better of changing my units (i have 2.5 magic aire in the basement).
So I went online and bought 30 pounds of R22 for $924 for just in case.
My cousin found the leak slow leak in the attic. Added 10 pounds of R22. Fixed the motor in the basement unit. Spent 7 hours doing the job and charged me $500.
My units are running like brand new. Because I gutted my house before I bought it and had both units put in. 20 years and counting very little problems so why change them.
Now if I'd got the same job done by the original company I'd would of spent $2700 just on Freon R22. I doubt he'd do such a fantastic job as my cousin. Because he took his time to figure out what was wrong with my unit which was iceing up outside and not cooling the house once it got above 85 outside
very cool bro glad to here that you did not get ripped off
@@TaddyDigest thanks you. I love your channel especially after this summer.. I'm glad the first guy scared me with the price of R22. Because even my cousin was shocked 😦 by me buying it for 924 for 30 pounds online. He said his company normally charges customers 150 to 200 a pound 🤔. Well I have 20 pounds left. With my slow leak found in the attic that should last me for awhile 🤔
What would you recommend for my setup? We have a 3 floor townhouse. No basement, first floor is on concrete. Our unit, however, is up on the third floor. Its a reversed system. Upstairs is always dying in the summer and comfortable in the winter while downstairs is cold in the winter and average in the summer.
One recommendation: your temp clamp should be placed 6” from test port and on the top of the line set so oils don’t mess with temp
I think you are reaching here a bit
@@j727100 hey, if you want to be a good tech and not a great tech then that’s your prerogative. The only thing stopping you is yourself.
@chrismunoz7156 well how can you argue with that
I will test this out. I'm going to place my clamp thermistor on the service brass portion of the valve and then 6" away. Then I'll switch postion from the top to the bottom. Record my readings to see if there is any difference in temp.
@@j727100 you’ll have to do it with every unit to see the correlation, it won’t happen every time. I was a proctor for TEP and they were very strict on how readings were taken. They’ll also teach you this in trade school
Anyone notice that not one of them floor joist have a hangar on it attaching to the beam? Is a nice HVAC system though!!
One of the most commonly overlooked A/C issues here in Florida is the air distribution. Overuse of flex duct is the devil.
It's all in the attic, block construction.
You mentioned about having a digital hydrometer and a dehumidifier i have both and not certain if my house has foam insulation or bit because there is spray in insulation in the attic. But what i can say is that the air coming out of my registers are roughly 70% humidity when the ac is running. I have a track home in se Texas built 2018. Any idea wth is going on? My free standing dehumidifier with built in pump just cannot keep up.
What about the filter? Merv on my in laws is like 1 and getting a lot of mud in evaporator drain lines now getting freeze ups . I’m trying to tell him to get something better but he’s worried about losing air flow? I have a 4 inch merv 11 on a standard blower and works great. I need one of those airflow meters!
AND that is how u get another subscriber :)
Sweet
Thanks man.
Happy to help
You just got yourself a call back because the customer can’t feel the air coming out of the vent.
Over time k-type connecters where it plugs into your meter. Those flat blade types. They usually don't have a good strain relief and you can take it apart. Cut back to fresh wire and re-attached to the two screw heads. I see those ones are not-re-buildable. Get generic k-type ends that are field wire capable.
It's nice when the basement is open and you can access everything but when you have a finished basement and very little access to the ductwork there's little that can be done in way of balancing ductwork and adjusting blower speed. If I went into someone's home and told then, Hey if you let me tear apart your basement ceiling I can optimize and balance your system by changing your ductwork/fan speed for a more efficient system. They would point me to the door and tell me to leave.
You also have to consider the customer's budget. It's not cheap to redo all the ductwork in a house and 90% of people will tell you NO.
It's a great install and it looks nice.
I am concerned when I hear that the units superheat is only at 5 degrees. If your superheat is to low or nonexistent you run the risk of liquid refrigerant coming back to the compressor and causing damage or it washes the oil out of the compressor which would also cause it to burn up and fail. I normally try to set my superheat at 10-15 degrees.
I still liked your attention to detail and I hope to learn a couple things from you in the future. Thanks for the content.
Something to think about. 12 to 16 degrees superheat. Do u follow the charge chart or apply the 12 to 16 degrees principle?
Is there such a thing as the return elbow to the furnace as too big ? Mine is 10" x 25" coming down to the elbow.
Am I understanding this correctly? No matter the size of the room, the supply vents should blow the same amount of CFM? If so, what should that be?
260 Psi high temperature pressure gauge (red). 20 cell per division.
I have a Amana AHVE36CP1400AA Inverted air handler that’s very loud. Can fan speed be lowered on it like in your video?
Most HVAC people I've seen, install, turn on and you never see them again. Never knew these details before. Want to install a system in California?!
Yeah people don't really commission anymore it's sad.
I'm pretty far away from california l o l
How do I find someone in my area who will perform a a detailed test like this?
Love the video, nice tips. That superheat....blower related? " I'll keep you cool if you let me" I'm going to use that ❤
Copywrited! Tad!
@@dporrasxtremeLS3 even if he did have a copyright doesn't mean you can't use it, you just can't sell for a profit as if you owned the copyright.
Nice install. And good video 👍👍
Thank you my brother
I am glad you're here
I have a new unit but some of the rooms upstairs are not cold?
Tad did you do the duct work? Nice job! Super great video, lots to cover! Details, Details!
yes sir thank you 😊
Ever since I got my TrueFlow grid for measuring CFM total, my Testo and Fieldpiece airflow, measuring tools, feel neglected in a bandit. The batteries are going to go dead inside them before they ever get used again..
I
Show more on how to do a temp split Tad. Plz.
Will do my brother
In Louisiana it hot heat wave
Hi Taddy, are you going to do another PulseX video after the likely launch this weekend?
Liked your Sacrifice videos. Would be good to hear another video.
I may have to give it a shot
I hope that it really launches
@@TaddyDigest
Great to hear! Yes, Same. We have remained Patient, and all our lives have carried on.
But its all about to get exciting now and the wait would have been worth it. I'm certain of it.
All the best.
Proud to be American
Was gonna say looks good if it’s 75 degrees but you beat me to it
I love my fast hard blowing ac.. my house stays freezing cold..
What do you do for a single stage? Here on the Gulf Coast, the humidity is so high and temps have been so hot lately.
He don't know he is a hacker
Hello, I have a bi-level home and cooler in the lower half (finished) I have a return vent on the other side of the wall just before my filter, question since my upper level is way warmer, should I close that lower return vent located near the filter ?
I would have to know what tonnage your equipment is
How much return does your equipment need based off of the tonnage
Then I could determine whether or not you could close off that return
But until then i'm afraid it may affect your equipment in a negative way
That's one way to do it, just not the right or most accurate way. You should have measured static pressure and compared to blower performance chart and started by adjusting the blower speed based on static pressure. Also all your ducts shouldn't have the same amount of airflow or velocity either. Depends on the manual J load calculation and the design of the home, and register location...
I have a question if you adjust blower speed on a variable speed motor will the blower motor still do the variable speed option?
Yes.
What happened to the super heat when you turned down fan speed? What happen to coil temp? What happen to delta?
I thought that was all in the video I will do a video that next time
Home owner’$ could learn a lot from this video
Good
Please share the video
@@TaddyDigest I tried to explain this to homeowners myself, but I don’t have the type of equipment that you have. I’m going to invest soon into those.
the return in our home is the interior of a framed out sheetrock wall its like a 2.5x2.5 chute up into the attic and the top of the shoot is a duct box. There is the backside of drywall, studs, and the concrete slab exposed in this space. Is this correct?
That sounds interesting
I would have to see pictures to be able to tell you if it's right.
Do you wanna click the join button and get my email? I will send it to you and then you can send me pictures.
I prefer to take static pressure and set air flow to 350-400 CFH per ton of cooling. With your second probe it will compute TEET.
very good practice I like that 👍
Without design conditions(manual j) , how are you achieving proper SHR from the equipment?
lol, 3-5* superheat, What happens when the filter gets dirty?
Tad i would like to know if you have different size registers in the should they all still blow the same or should different sizes blow different speeds ?
Just curious
They should all blow the same feet per minute
try insulating the supply. No radius on the supply plenum elbow??? No turning vains???
You need to add joist hangers where joist meet header beam.
Last I checked, this isn’t a carpentry video.
Good catch.
My Honeywell pro series & My temperature is not reading room temperature going high temperature by itself & it takes forever my unit or or coil my coil is 20 years old already one of the rooms not blowing enough cold air only things only night time around 10 pm clock it does go down nighttime only Andy daytime my temperature goes up high temperature what to do I think it needs a tune-up check up I hope it's not that was it something else wrong with it AC I like your videos I'm learning how to do it @TaddyDigest
Can you show us how to take a static pressure reading and explain to us what it means
yes of course I will get that on video soon
@@TaddyDigest Will be watching!
I wish I had someone to come to Chester County and check my like that I can trust.
Chester south Carolina?
PA?
Same
Is 700 the best target airflow for pretty much all systems or just this house in particular? Also, I know that if a system doesn't have enough airflow then it can freeze up, so does lowering the fan speed not cause future problems?
In between 400 -700 feet per minute
As long as you monitor the Pressures and adjust the charge properly. You will never have a problem.
wish my upstairs room blew 1000 ft/min. its bakin even with the downstairs dampers and thermostat at 70
I’m not a technician just a home owner. Had new system installed (Canada). 1.5 ton AC with 2 tone A coil. They didn’t set my fan speed but I do know how to adjust the taps myself.
Currently it’s on 796 cfm should I knock this down to 596. The old system that died was a 2 ton. They said I was over sized. 1300 sqft house.
I did try it briefly but I only saw at the register about a 1 degree drop. So at the lower speed I get 53.7
Is 200 cfm really worth the reduction. I’m seeing the upper floors warmer a tad dripping down the cfm
I would keep it where it's at
So would you change the fan speed for winter months? I may have to get one of those units as our ranch is not balanced very well. We installed a damper to push more air to the furthest end from the system.
im not a tech, but i know enough to be dangerous. your thermostat will use different speeds for heat and cooling, faster fan speed for cooling due to heavier cool air. the cooling speeds may not be optimal, and still need to be tweaked.
On this system, you can see that the controller board has separate fan speed jumpers for heating and cooling. Generally, you'll want to have a higher airflow for cooling. If you determine that two speeds are needed for cooling and heating and your system doesn't have separate heat/cool speed settings, then yes you might want to adjust the blower speed with the season change.
So the thermometer/hygrometer determines if there's too much air or too little cfms?
No a thermometer tells temperature and a Hygrometer tells humidity.
Adding a dehumidifier is just wringing out more moisture right?
yes
Wow…..have never heard of this!!! Got a new follower bro!
thanks 👍
I have had this issue for a couple of years since I bought the home. All my rooms in the back of a single story family house that’s not even 1500 sqft don’t get as much airflow as the living room and kitchen. The middle room of the three in the back hardly gets any airflow out of the vent. How can I get that fixed, my child is in that room and I live in Texas so it’s hot in his room in the summer and cold in the winter ?
Really need more info I can't really help you with this problem through the comments I can give you advice though
Check the duck size
Check the air flow feet per minute
Check the size of the unit and the amount of vent you have
Watch my members only video on duck sizing and air flow and duck design
Join
ua-cam.com/channels/uMyjTVlkM4xZ5z_eSyoB1w.htmljoin
I'll have to look at the air flow control on my furnace unit. I feel like my blows to fast as well.
seriously, don't. if you slow it down too much it may not cool well enough or it may freeze up. any airflow adjustments should be immediately followed by checking refrigerant pressures.
Need to install a tee after the trap
Maybe I just missed it, but I don't think you explained why this improves things or how it works. I get that the lower blower pressure is quieter, and you said that it also improves the dehumidifying effect, both of which are nice but is there some significant improvement of cooling effect that results from lowering the blower pressure?
You showed that the air coming out is cooler, but of course it's both the volume of air as well as the temperature difference that determine the total amount of cooling effect. Is there some sort of optimum tradeoff between CFM and temperature?
As for how it works, my guess is that because the air is moving through the plenum more slowly, it has more time to get cooled by the evaporator coil. And, of course, the colder the air is, the more humidity drops out. Is that the whole explanation or is there more to it than that?
You hit the nail on the head with the last sentence
Good deal
You understand
Not only did I increase the capacity of the equipment and correct the c f m across the return grill.
But I provide better comfort and remove more humidity
Great video... would this cause a brand new trane to drip small amounts of water onto the air filter?
Any ideas?
@@KBradAdams Generally that means a clogged condensation run-off pipe.
@@8307c4 that was cleaned out already? It’s more of a drip type thing but on the filter! I read it could be coming from the coils bypassing the top drip pan?
I moved into a condo where the air is not balanced in the upper level. It’s about 10° higher on a hot day. I’ve determined the problem is the air return. It just does not pull hard enough to return air from the upper level, but does fine at the main level, there’s about 40 feet of run for the returns in the upper level. Is there a solution to this?
Absolutely there is a solution
@@TaddyDigest What do you suggest? No one has been able to offer one.
Cheap filter
@@yourmedicareguylarrybelt7792does the upper level have a thermostat or is the thermostat on the lower level? Would probably do better if it was zoned as well. It's prob a combination of the long return, also if thermostat is downstairs it's gonna satisfy by that temp and may still need more run time to cool the upstairs down. Zoning it would help. What size are your returns?
1,2 degrees cooler but little air coming out of the vents this may runs longer to cool the house
@@Icanfixstuff If you run slower, the power consumption will be lower so you can run longer with increase your power bill. The advantage of running slower and longer is that dehumidification is better, so you can get your house to the 40%-50% humidity. A lot more comfortable and avoid mold.
So 5 degrees superheat is too low. Not enough air over the evaporator will cause liquid refrigerant to wash out your oil in the compressor making it fail. The superheat was moving all over due to the TXV hunting around. In my opinion you just made a perfect expensive early compressor failure. Always keep superheat at 10 to 20 degrees. Your sub cooling looked good at 10 degrees.
Exactly. Suction temp should never be below 50°. That cold refrigerant will hit the hot scrolls and make some money for the next tech. Unfortunate for the homeowners. Yes they'll be getting better dehumidification now but at the expense of a compressor. If it was me I would have balanced the house opposed to cutting down air flow. That would be the last resort. And on the other hand he should have waited 10mins or so for the refrigerant to make a complete cycle through the system and show the discharge air temp to be lower than after a short walk back up stairs to your velometer. Just my two cents.
Exactly what Ruck said.. 90% of ac installers are bogus...
Yeah 5 is cutting it a little too close for my comfort. Also you shouldn't need a dehumidifier on the main floor or anywhere in the house if the unit is sized properly and set up properly. Maybe one for a sealed crawl space but not the house.
We have a newly constructed house (2 story) foam insulation and the airflow is super inconsistent per vent. 2 rooms stay cold (20 degrees temperature difference on airflow coming out of the vent. House was brand new we moved in July of this year. I opened the door to the attic and he was super hot up there (not a lot of space to move around). Any advice?
Hello I need help i have a goodman condenser
Low side has 120 psgi and 27 super heat but on high side has 180 pressure head. Is not cooling the apartment . What should i do. Thanks
Sounds like his low refrigerant check the refrigerant levels
@@TaddyDigest I forgot to mention that is an R 22 unit
oh ok check cap and could be compressor problems check volts to motors
What is super heat? How does a lower fan speed make the temperature cooler?
Super Heat Can signify how much refrigerant is in the evaporator
Because if you lower the fan speed the air flows slower across a cold coil therefore lowering the temperature.
@@TaddyDigest thanks. My Heil air handler does not have a circuit board on the fan housing, or perhaps it is somewhere inaccessible
Does system use a TXV or fixed restriction?
txv
What’s the benefit for this other than human comfort?
Energy cost
The 30% decrease in air flow with the 2 degree change doesn't seem like a "win" to me. If it would be 100 out like it is here that system would never keep up. Why do you feel this is better?
colder air is always a win my friend plus the Feet per minute was way to much according to TVA standards for comfort and efficiency
How does slowing the fan speed down make the air coming out colder?
Lowers the temperature of the refrigerant
At the indoor coil
@@TaddyDigest thanks man
Drop the fan speed will provide more dehumidification plus decrease my supply 5 degrees, I could use your service in SW Florida. Six visits from my two year newly installed 16 SEER Goodman HP and they still can't get it right.
What is your average indoor relative humidity? what’s your average run cycle time?