Diagnosing Inefficient Systems, and Trying to Make Them Better

[@HVACGUY]

On the first one, my amp draw was all over the place. On the second it was well within normal range.

[@gor312]

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.

[@ronroberts7566]

Air Flow - if multi speed fan, you can go to next lower speed and operate 30 min to see how improves Q total heat = 1.08 x cfm x Delta T

[@TheFoxygrandpa69]

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.

[@HVACGUY]

Ill try that

[@natepeterson7145]

That's a great idea! @Jer Bear

[@jeremiahhively3025]

That would be awesome

[@Brad.W]

Motorola phones have that feature built in can triple tap your screen and it immediately starts recording your screen and saves it to phone storage.

[@tonyrhoton6613]

I agree myself barley tell wat ph. Says

[@billmiller5075]

I would check return temp at the return plenum; and also blower speed

[@stephenbierlein2517]

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.

[@johncspine2787]

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..

[@adamhyche8947]

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.

[@dunnar90]

3 degrees seems like plenty. At what temp difference do you personally condemn a filter drier?

[@allanbrito13]

@@dunnar90 id like an answer to that too. Had one the other day with a 1 degree differential. Checked it due to a restriction

[@mordeth999]

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.

[@rileydavis435]

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.

[@Jon-hx7pe]

This kind of troubleshooting is what separates the sales-tech/parts changers/refrigerant topper uppers from competent techs.

[@Ricky32908]

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

[@Crazywill210]

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.

[@deanmartin1966]

I was thinking the same thing. The blower speed was on too high. But I’m not there so it’s just a guess. Lol

[@OleRazzleDazzler]

not enough data to tell.

[@OleRazzleDazzler]

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

[@rubenguzman6144]

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

[@rileydavis435]

I did the coolsaver program in Arkansas. Before I moved to Montana.

[@trevormangus7832]

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

[@MariosACandRefrigeration]

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.

[@Brad.W]

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]

Like car some think its got gas its ok oil wats that lol.

[@Brad.W]

@@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.

[@hvaclifeatx7012]

Great job k. I just had one like that the other day,, now I know what to look for,, your video ALWAYS help👌🏻

[@tristanwilson2560]

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

[@MarcHord-mk5ff]

Check return air at unit, not at grill. Looks like hot return air to me as well!

[@MariosACandRefrigeration]

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 ?

[@larryehrlich57]

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.

[@jasonaguilar4929]

Great videos really helps also picked up the Milwaukee flash light really like it thanks for all the video 👍🏾✌🏾

[@stephenbullock1443]

I going guess the reverse valve might be hanging up causing bypass! 🤔

[@joshtaylor8711]

Heat strips on the first unit? maybe first stage strips are stuck on? I've had that happen and run the bill up, low delta

[@OleRazzleDazzler]

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

[@spymoocowgaming]

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...

[@scottallen5182]

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!

[@rwcasto]

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!

[@rodgraff1782]

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.

[@OleRazzleDazzler]

i would of like to knowj the airflow.

[@mikemarshall1394]

Is the filter media restrictive. Higher than Merv 6 may be fighting your airflow

[@daleborg9070]

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?

[@jynnandtonnyx]

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 :)

[@HVACGUY]

I was on site of each of these for over an hour.

[@jamminwrenches860]

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

[@user-ln7of9gs4s]

Who’s Brandon?

[@gamewizardks]

@@user-ln7of9gs4s Brandon is your current president.

[@user-ln7of9gs4s]

@@gamewizardks in what country?

[@gamewizardks]

@@user-ln7of9gs4s The left doesn't meme.

[@MariosACandRefrigeration]

you can reduce speed for better delta but it will remain at the same capacity 77 deg RT.need bigger condenser.

[@thesilentonevictor]

To me on the second one the ahu coil looks dirty I agree both need a deep clean an then we can judge system performance as per manufacturer

[@Bullseye-u7k]

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

[@brnmcc01]

On 410A yes. That size 51 was for a 1.5 ton unit.

[@crashwrench]

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?

[@HVACGUY]

I guess you could

[@johncspine2787]

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..

[@Bryr2112]

how were your amps on the compressor? were they lower than normal?

[@TheFoxygrandpa69]

I haven't seen the BBQ brush on the coil technique before. That actually work? Seems like it would just mash the fins up.

[@HVACGUY]

If you’re careful it don’t mess up the fins.

[@TheFoxygrandpa69]

@@HVACGUY right on thanks for the info. Ill give it a shot.

[@vincemajestyk9497]

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]

Oversizing a coil does not lose you capacity, it improves efficiency. I oversized coils up to a ton and half with great results.

[@vincemajestyk9497]

@@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.

[@joeburner7120]

@@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.

[@vincemajestyk9497]

@@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.

[@mwdub02]

@@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.

[@Demy26]

2nd house definitely needs insulation.

[@David-yy7lb]

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🤦🏿‍♂️

[@th-wt5pn]

How did you get your display to show that analog view and then you switched it back to the regular view?

[@HVACGUY]

Different app. Measurequick

[@th-wt5pn]

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 👍🏽

[@michaelhediger9088]

What is the pressures for high and low side if pressure are close to equal you have a bad compressor

[@maintenanceman1015]

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 .

[@johncspine2787]

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..

[@BarneyBeauregard]

The orifice one had too much freon, not too little! Been there.

[@tonyrhoton6613]

My thoughts also i get in 2 over gased units going behind a certain company with young help

[@luissalas9270]

Good video, i pump it down and then turn it off . It should hold

[@x01e]

What was the fix?

[@throttlebottle5906]

$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).

[@JunkTech89]

I have had heat strips short on one side causing half of the heat to run causing hi power bills I check for the heat on both sides of the circuit now

[@hvac4u2]

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.

[@deanmartin1966]

Just wondering if lowering the blower speed would of reduced suction pressure and increased delta T? Your thoughts?

[@HVACGUY]

Yes, it would. But wouldn’t help with efficiency.

[@deanmartin1966]

@@HVACGUY good point

[@tristanwilson2560]

@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.

[@oxygon2850]

Leesburg, Georgia

[@TheWilber09]

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.

[@joesolis8423]

Always great content, what part of the country you service?

[@lancelawrence3259]

Nice work

[@rwroundt55555]

Thanks!

[@HVACGUY]

Very much appreciated!

[@mattbilodeau2433]

What type of magnetic lite do you use

[@kevinkrug466]

Curtis wears jeans everyday day of the year, he don't care if it's 102 out he's wearing them jeans

[@colbraddock9913]

Pants and long sleeve shirts keep you cooler than wearing shorts and a short sleeve shirt.

[@gamewizardks]

@@colbraddock9913 Not sure about that.

[@colbraddock9913]

@@gamewizardks read up on it

[@tonyrhoton6613]

All the crawling

[@briancarlisi2224]

Your Fieldpiece App is steady… mine constantly dropped the probe signal today from 4’ distance. Any suggestions?

[@MoonRambo702]

Could be ur phone

[@Paulie1232]

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....

[@HVACGUY]

I may be going back to the first just to doublecheck. So, I may try. Appreciate the input.

[@BryanI00]

Kind of odd having a reversing valve and a piston. Was it a heat pump turned straight a/c?

[@HVACGUY]

Matching system, still a heat pump.

[@caru3257]

my system is an hp and it has a piston.

[@BryanI00]

I didn't know that was thing. Learned something new! I'm not an HVAC tech, I just enjoy the videos.

[@throttlebottle5906]

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.

[@mansourramzey7711]

What brand tape were you using. Tks

[@HVACGUY]

Not sure

[@mansourramzey7711]

@@HVACGUY what do they call it , so i can find it. It sticks real good

[@daddygc5814]

Foil tape,you can get at homedepot

[@brenninwatts1249]

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]

Yes most of these condensers will have scrolls in them and it is okay to pump them down.

[@brenninwatts1249]

@@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?

[@tristanwilson2560]

@@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.

[@MarcHord-mk5ff]

Airflow airflow!!

[@topher8634]

Sounds like summer expansion valve is over feeding.

[@davidtaylor7174]

Stupid question. I didn't hear you say anything about checking blower speed. I assume they were on high.

[@edgarlezcas7287]

New compressor needs?

[@JHACbiz]

make sure the strip heat isn't coming on.

[@allanfolkes6019]

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

[@HVACGUY]

You can never be sure

[@braintumor943]

Nothing wrong with that compressor on first one

[@chodge8366]

amp draw?

[@HVACGUY]

On the first amp draw was all over the place. On second it was normal

[@MariosACandRefrigeration]

@@HVACGUY he is talking about the heater being on on the AHU

[@johncspine2787]

Seems dumb to put cooling units in flaming hot attics along with the ductwork too…

[@DC-do8vd]

Could be too high of a blower speed.

[@gamewizardks]

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.

[@Sctronic209]

👍👍👍

[@hartsfire5706]

i so hate that kind of Condenser you can never really get them clean and they don't seam to col right here in the north east.

[@khx73]

The spine fin? Mine cools great here in the far north east

[@tristanwilson2560]

You have to take them apart and wash from the inside. Use strong chemicals and take your time.

[@thelazyfishkeeper2730]

so they run and cool ,just not at 100%. i know you are not happy with the outcome. stay well see you next time.

[@tonyrhoton6613]

Imo. Those evap coils suck not enough surface area

[@stephwaylonwells3218]

👍

[@scottallen5182]

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.

[@chrissipple1018]

When you say temp drop do you mean Delta T, and do not pump a scroll compressor into a vacuum it may short out the terminals.

[@HVACGUY]

Yes delta t and temp drop are the same

[@braintumor943]

It has a bad reversing valve, charge them 1000 dollars to take it out and let them run on straight cooling with strips

[@realestateservicessaleshea99]

(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) 🥃🥃🍺🍺🍺

[@carlsmith5919]

Suction valves going bad.

[@harshmehta374]

Any job pls help

[@seanwestervelt7503]

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?

[@carlneuber4994]

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.

[@tristanwilson2560]

Idk how you passed high school with that spelling 😂