Seems like a possible issue on both of these is a reversing valve that's not sealing and bypassing hot gas into the suction port. I would have tried to cycle it a few times and see if the behavior changes any. Checking for temperature drop isn't reliable at all -- the valve may very well be in the right position, it's just not sealing because of wear and/or contamination.
You never checked to see if the pump down held, after turning off the power. It could be discharge valves or reversing valve on the first one. On the second one, you could have blocked the condenser air flow, to bring the discharge pressure up, and see if the low side tracks up with the discharge pressure. This would indicate bad valves. On 22 if the low side went to 85 with the head at 350 or lower, we condemned the compressor as not pumping properly. Sometimes this doesn’t show up until it gets hotter outside.
I don’t know if in Georgia if y’all have Energy for power company. But if y’all do u should check in to the coolsaver program. The power company pays u to go do a tuneup on the ac unit. It a good program to make adjustments to to the unit to make them more energy efficient.
Yeah..my 36 dollar electric bill a month, 68 degree inside, 105 outside days are over..my swampy supply cord started an attic fire, I got a new mini split system installed, I’ll let you know next summer how I fare..
My home unit does that same as the 2nd unit I have to close discharge valve recovering refrigerant and quickly open it seems to fix it til the next season (Been doing this for years now ) I assume it’s a small piece of trash in system getting stuck in txv
Seems like there should be a specialized brush that’s hollow with suction/vacuum on it, or rather in it, so you could dislodge stuff and suck it out at the same time, and a reverse switch for blowing too. Different bristles for different coil fins..
On that 1st one, I think it might be an issue with the evaporator coil. I've seen this many times. A partially functioning coil that likely has a restriction in one or more of the tubes coming off it's distributor. Every time that I've seen this, a coil replacement fixed the issue.
I've seen that before. Old guy I've worked with along time ago. I remember he changed reversing valve and didn't work. Then he turn down blower speed And delta T went from 13 to 18.
the first unit would of been q good one to check that static with them fancy new probes you showed us yesterday brother. but those types of cals send us down rabbitt holes
It would be helpful if you had a list of contractors that you could give to the homeowners. Contractors with a good reputation...and have those contractors do the same for you.
I would look at amps. A week compressor usually will have low head and high suction. Wouldn't show a big problem in mild weather. When hot it is a real problem. Usually means had dirty condensor problems in past.
It's amazing to me the number of people who don't keep an eye on their Air supply I checked my filters weekly any sign of discoloration they get changed immediately.
@@tonyrhoton6613 Mate. Dead set. I work for a BMW dealership 30 some odd years ago as a lube Tech it baffled the hell out of me the number of people who would put 60 or 75,000 miles on their brand new expensive BMW and didn't know that they were supposed to change their oil every 3000 miles and would only bring it in because it was time for their first checkup for the engine started sounding like it had a bag of rocks in it. I had many vehicles where i'd pull the oil drain plug and nothing came out but this jelly like substance that resembled tar if that and they wonder why their engine is knocking and get even more pissed when they find out that warranty wouldn't fix it because they were fuckwits and blew their engines up whether it was intentional or not because no oil changes. Just like these new Tesla or EV's people buy them and think that they are maintenance free just because it's a battery powered vehicle my wife happens to own one and it has fluids just like any other car that has to be changed every 6 months to a year. The electric motors that drive the wheels have some form of electrical or hydraulic oil in them that have to be changed annually or so many hours or they begin to overheat and burn up. Even the battery banks themselves are cooled with some type of liquid/gel mixture that is circulated around them when the vehicle is running to keep them from overheating.. my wife bless her bought into the Tesla scam thinking it was going to be cheaper to own the maintenance on that thing is 10 times more than what my diesel truck is it cost more to keep that thing running in a year's time then what most people spend on gas in a 2 or 3 year period. Contract from Tesla says that the battery has to be changed every 50k to 100k hours those things are like 15 or $20K a pop and most of them have 3 banks.
Did someone else do some work on the system just before the electric bill went up? Did someone change refrigerant. R-422B? Did someone introduce air into the system?
At 4:40 the reason I carry black duct tape is to always ALWAYS tape the foil thing to the door, it always comes off and I’ve always been worried of that happening or the foil paper gets sucked into the blower, the later has happened
When testing differential across a reversing valve, it is best to measure suction to suction since you will naturally have a differential if measuring discharge to discharge. Also; it’s ideal to place your probes at least 6” equivalent from the valve body due to it being brass and naturally giving off/ absorbing heat. If your suction line inlet back to the compressor is warmer than the suction inlet to the reversing valve then you are leaking discharge gas internally which is the most common reversing valve failure (plunger failing to seat/ shift fully into place). Typically; I will use anything over a 3 degree differential as caution or recommended action of replacement if I can’t get it to reseat by shifting the valve back and forth.
Like your above comment, but 3 degrees is way too tight a range. A 5° temp difference is the minimum difference before concern by most manufacturers. Filter driers having a temp differential of 3° or more IS a legit concern.
Are you kidding me a freaking hot water heater in the attic, when it starts to leak the ceiling is damaged....what in the hell are these home builders thinking about it's bad enough that the hvac is in the attic🤦🏿♂️
on the first one you are supposed to check delta in the attic 1 foot away from the AHU.thanks for sharing.check amps on AHU.69 deg return is very cold ?
You should record your screen with "mobizen" and put it up in the corner of the video so we can see the pressures and stuff real easy. It'd really set you apart from everyone else. You're already my favorite but just a suggestion.
I downloaded it and I am setting it up now. Thanks for the tip and keep the good videos coming. Im out of Maryland and I watch your vids all the time 👍🏽
My electric bills have doubled. After investigating part of it was the high temps but most of it was price increases at the electric company. Check last year's bill to this year. Thanks Brandon
I had an old 2 stage trane r-22 unit that was giving me 95psi on the low side and 375 on the high.... 12 degree temp split in the house. My first inclination was that it was overcharged-however after checking the compressor it would not pump all the way down. Homeowner said they have never had anyone out to service the init since 2012.... WIERD!
$200 to $500 electric bill jump, that instantly screams heat strips are on and shouldn't be or it's suddenly pulling hot attic air/dumping cool air in crawl space(assuming it has one).
Definitely worth a look. However, the 7 degree rise on true suction at the reversing valve , low t/d with high suction line temp/ pressure shows the capacity loss.
or you have heat strips on. i have seen that before even being downstream from coil that it can gain heat from heat strips having failed sequencer or contactor
on the second ,they install a unit 1/2 ton short,when you change condenser to the larger r 410a with the piston to match,and you will get 18 to 20 delta.
That was really barely any insulation in that attic. My friend bought a house 30 years ago that had 2 systems, a 3 ton for the first floor and 2.5 ton for the second. He was the original owner. For years, like 8 years, he said the upstairs struggled to cool down. Had multiple HVAC service visits over the years. Finally, one tech checks the plates and tells him when they built the house they mis-matched the evaporator coil and pump by I believe it was 1 to maybe 1.5 ton. He said the most you could get away with is half a ton. If I remember the coil was over capacity of the condensing unit. He had a new system installed and it worked fine. He said the builder just pulled 'whatever' they had on hand in the warehouse to get the job done. Most people would 'presume' that the original installation was correct which is why the problem went undiagnosed so long. Sometimes when a system is spec'd and running at capacity or peak operation it's on the ragged edge of acceptable with no margin.
@@joep4143 They were mis-matched and there was a problem that went away with properly matched components. There's a reason why they have ratings. If the coils aren't matched it's not operating at peak efficiency. If one coil needs to be upsized then the system wasn't sized properly in the first place. Laws of Thermodynamics dictate that mis-matched coils ARE NOT operating at peak efficiency. They just aren't. That condensing unit is going to run A LOT longer trying to keep up with the evap coil and in high heat load it may never. There's all kinds of reasons why installers try to re-invent the laws of physics. Putting in a smaller CU to make it run longer may control humidity, but it can't keep up with the heat load and wastes energy. Outside pressures will not be optimized with a larger coil, and if it's a heat pump system you're not going to have enough of a system charge to properly operate in heat mode. A PROPERLY sized system is always the best answer.
@@vincemajestyk9497 Most manufacturers have coils like 1.5 to 2 tons. 2.5 to 3 tons and 3.5 to 4 tons, so half a ton won’t make much of a difference. You will definitely get better humidity removal from a larger coil. I do agree that an undersized condenser with a bigger coil is wrong. Do a load calc, make sure that your condenser is sized for the space and you can upsize evaporator by half ton or 1 ton with great results.
@@joeburner7120 Yup, I agree, 1/2 is OK. That attic was crazy. Almost NO insulation. Crazy because that blown in stuff is cheap. I saw that hot water tank in the back too. That must be fun to change out. One of the worst things too are those attic fans that pull conditioned air OUT of the living space. Those fans are the biggest scam. The heat is all from radiation anyway so that fan isn't doing anything. I think they're illegal in GA to install they're such energy wasters. The attic is probably the worst space for mechanical equipment but you gotta work in the real world.
@@joep4143 oversizing evap coils will cause more problems in humid climates. It’ll never work right when it’s time to dehumidify the air. Yes it’ll pull the temperature down put will suck at dehumidification. Edit: it’ll be more efficient as far as I know. A half ton more is fine, but bigger than that you’ll start to see humidity problems.
first ones a bad reversing valve...or at least one thats sticking probably due to the compressor windings breaking down. Id meg the compressor out and see if that tests poorly and then throw in some oil additive and cycle that reversing valve coil probably 50-100 times and see if I can improve my readings any...
I had one the other day like that and it was the wrong meeting device size.... It was a 2 t Goodman Size 51 it should have been A 57 I changed it took care my problem
I have seen where a piston lodges in the cylinder and doesn’t seat properly, that’s would give you low super heat low sub cooling High suction and low liquid line pressure my solution was installing a txv, but I’ve also seen where a compressor pumps down but had bad valves and low capacity, high suction and low liquid line pressure, good vids like to see what your solutions were.part2
Could you please tell us roughly how long you were on site for each call, and if you checked amp draws and capacitor? Would there be any indications that you would have needed to? Thanks :)
we as technicians are always looking for the magic bullet to solve the problem. A lot of the time we are actually dealing with a multitude of smaller issues combining to make a large problem. I think this is the probable problem with these systems, and it's not what the customer wants to hear!
On the first call you could be pulling in hot attic air from the return causing your suction pressure to go up. Also when you have a piston there is a superheat calculator app that calculates the exact superheat needed at that time by using wet bulb and dry bulb temps. Keep us updated
Hi, in the second half Video, would it help to use "spray foam" to seal the wood joints and then use duct work tape over it? if building a "air return duct ", Would it best to Insulate that Return?
many of the pistons are in fact a sliding piston/check valve combination. gas flowing in for cooling, the piston slides in closing a teflon seal against a seat and meters it via the orifice. reverse the gas flow for heating and it pushes open and bypassing freely. there is a problem with that design, the seat/piston seal can get dirt or waxed oil gummed in place and not shut fully, you'll end up with coil flooding in cooling and low efficiency/pressures wonky. it's possible both systems could have the same issue, even though one isn't a heat pump. the coil/piston setup may be the same for both and it can migrate open slightly with junk sticking it. the heat-pump model may free up and start working if it's reversed a multiple times in a row.
Curious if you did a outside temp and attic temp . Was hoping you where going to use your new gauge to check air flow threw that dirty evaporator coil .
Yeah, I was thinking an attic temp would show at least broadly if there was a ductwork problem..I say it again, I think ductwork and cooling unit being placed in the absolute hottest area of a home is counterproductive at the very least..
@R P I agree with the delta T. Also shouldn’t have put refrigerant in on the first call with those pressures and sc/sh readings. Your problem I think is with airflow or possibly hot air from attic making it into the return somehow. Maybe flex came off partially.
Are these scrolls compressors you're pumping down? I've always heard scrolls shouldn't be pumped down. If they are scrolls is it okay to pump them down like you did for a quick test?
@@tristanwilson2560 From what I've read scroll compressors use the refrigerant as an insulator and pumping the unit down could short out the compressor if pulled down all the way or pulled into a slight vacuum. If pumping down a scroll i've heard to pump it down to where it is almost empty and then recover the rest. Why do you say it's okay to pump down scrolls?
@@brenninwatts1249 what do you mean by insulator? Compressors use refrigerant to lubricate and cool itself. I’ve pumped down many systems with scrolls and never had a problem.
Airflow? And the temp probes for delta need to be as close to the evaporator as possible. Everything is more than likely working just as it should the design Temps are just being exceeded with higher than normal temperatures as is the case with the entire US right now. Do the btu calculations with enthalpy and see how close they are to being on the money for delivered btu's Edit. What is the temp split supposed to be according to a chart based on Temps? Second edit. The attic duct work could be picking up so much heat ( measuring closer to the evaporator) it makes the temp split look worse.
There is nothing wrong with these systems. Both need a deep, I mean a deep cleaning on the condenser and evaporator....not just water, you need to use chemicals and let it soak in and let chemicals do its job....
Are you sure it's only 22 in that system if someone came to top it off before you and use the wrong gas the mix of the 2 could cause that suction temp your seeing they would have put just enough to stop it from icing but the mix would be like that possibility is there if all else fails reclaim and rehash with 22
Curtis, how did you check your air flow. Excess air flow can along with a dirty condenser can cause these issues. With no return static loss, you could easily have high air flow.
The insulation, while an energy efficiency concern, could not have made the electric bill nearly triple the last few mos. Something else had to happen. Even more than Joe Biden. What actually changed?
(IMO) This is the problem when you should oversize the unit a little. The one with the reversing valve the valve should be addressed if it's bypassing. (IMO) 🥃🥃🍺🍺🍺
Honestly I don't know how you stay in business. I would love to see you tech training credentials. Clogged coil equals low suction. Simple check was fixed orifice close off high side and pump down unit.