How to Check HVAC AC Compressor

[@WordofAdviceTV]

Hey guys! If you think the video starts kind of abruptly, you think correctly :) I accidently deleted the intro portion of the video from my computer. You’ll have to forgive me for not wanting to re-film it. Here is the script for the missing part if you are curious to know what you missed out on: "In my AC fixing videos, in the comment sections, often times I explain to people how to check their compressor to see if it’s bad or not. I finally decided to make a video of how to check your compressor which I can reference people to instead. Before we begin, I just want to make sure that you checked your capacitor before you start suspecting that your compressor is bad. If the compressor capacitor is dead, the compressor will not start. The capacitor is the silver cylinder looking thing right here. (points to the capacitor) Since this video is about the compressor, I wont be explaining how to check and replace the capacitor right now. I do have a video that shows how to do that though, it can be found in this video’s description. After you have verified that the capacitor is good…. (This is where the video begins) How to Check and Replace a Capacitor: kzbin.info/www/bejne/b4uql6l5YrWAjbc How to Troubleshoot A/C Step by Step: kzbin.info/www/bejne/raukcmeaodWSbZI

[@SakeEgo]

Spent 5 hours just to learn that my contactor was bad. Only guy that showed me that in my search, thanks.

[@omma-llama7860]

Hi. I'm posting here to say "Thank You!" ... you see we had been told by a local contractor that out old r22 condenser was shot and our entire system needed to be replaced. I came across your videos while doing my own research, and after watching about four or five of your videos on outside units, I was able to go outside and, for about $20 in parts get my old one working again. In my case, I had a bad 5 minute delay board. I much prefer to bypass the board then spend 6500 on a new system. I know it's coming in the future, but I'd like to get as much life out of this old system as I can. Thank you so very much.

[@WordofAdviceTV]

You're welcome! Happy to hear that your unit lives on! May it have many more good years before it retires ;)

[@chris.5434]

Now that same system cost almost 10k if not more. You waited to spend more money later.

[@mwjr2135]

I know I’m late but how do you bypass the board.. I’m going look it up. You telling me won’t hurt anything.. Thanks in advance.

[@bingoboppins9875]

How much longer did that last you?

[@Jon-fj7yk]

Post video how to by pass board

[@rachaelflaharty]

Thank you very much! My Husband was able to check the wires, and one was burned. He was able to replace it and fix it for free!! 😊

[@bsargent2065]

THANKS TO ALL YOU KZbin folks that take the time and effort to help us DIY folks. You probably have no idea how much your information is used and has helped others find out whats wrong and how to fix or investigate it. THANK YOU THANK YOU THANK YOU.

[@carlosa.avalle528]

I've done a lot of DIY repairs in my life but had never tackled AC problems before. AC systems are pretty intimidating but with your videos I was able to isolate the problem to the control board in the attic. A loose common wire may have been the culprit that would only manifest itself on the hottest days, intermittent problems are the worst. After hours of chasing the problem a simple turn of a screwdriver did the trick. I could not have done it without your videos. My hat off to you and I will be sending a contribution to your channel as I figure it has saved me hundreds. Thank you!

[@frankhernandez7827]

Thank you for sharing your knowledge. From a new home owner you have no idea what this means. Saving homeowners money is a blessing especially in a time like this. Thanks again for your time and God Bless.

[@RicardoRamirez-yj3sx]

Someone had already told me this method but wasn’t too sure if it was really accurate. Watching your video really helped. Thank you sir keep up the good videos. Well appreciated

[@georgepapasozomenos6336]

VERY VERY GOOD YOUR THE ONLY ONLY ONE EXPLAINED VERY WELL THANKS A LOT

[@marshallvincenzo3514]

Instablaster...

[@josealfaro888]

I am an electrician. I love your videos. Thank you.

[@T3chGuy007]

I just want to say that your channel and especially all of your air condtioning videos are extremely informative, helpful, and easy to understand. I've watched all of your AC videos and this has allowed me to change my capacitor and contactor without having to pay someone to do it! Unfortunately, my 15 year old AC has died once again and after watching this video, I believe it is my compressor. I have continuity on all three pins to ground so I think it's time for a new AC unit. Anyway, thank you again for uploading such awesome videos! Keep up the great job!

[@heber019]

you guys are amazing!!! I have to make some jobs with a new costumer and I literally had no idea how the aircon works till y saw your videos, now I feel more confident!! so the meaning of this text is THANK YOU and I wish you all the best!! course you have one more subscribed

[@WordofAdviceTV]

Thank you! :) Glad you found the video helpful!

[@joshevans969]

Thank you so much for these videos I was able to diagnose and fix my AC and only cost me $26 for a new thermostat

[@jimbola77]

smart kid thank you for sharing their partner a good job, God Bless!!!!!!!!

[@raybaker3578]

Thanks for the video saved me the cost of a weekend service call ( bad contactor ) I did not know about the test button!

[@Noelg14]

I actually learned something right now. Thank you dude keep making these awesome HVAC videos

[@WordofAdviceTV]

Glad to hear that! :) Thank you for watching and commenting!

[@jollyscaria1922]

Vrey good seftey

[@boblevey]

You are so good at explaining all of this!!!

[@dmonmitchell1357]

Your videos helped me out of confusing problems! Thanks bro!!!

[@jaquiebean8669]

HIM: make sure you check for voltage again a third time because I don’t want you dead’ ME: carefully placing the screwdriver on the grass, walking slowly back to my phone to call a tech. Decided to live another day for a different battle. Know your limits. Lol

[@sunset3052]

🤣🤣🤣

[@blackshirt5530]

Thank you sir! Your videos save people money and piece of mind!

[@Josemaldonado-qj6ss]

one of the best video i seen wow if i have to send a tutorial video it will be this one thanks good job !!

[@KhaledLK89]

Future AC/Refrigerator here. Thanks for the videos. They do a “ Ton “ pf help.

[@Froggability]

What a crazy place to mount the compressor! Bit tricky to check the terminals

[@DHgozwitJC]

Hi Jay. I love your videos, and even my 5 and 7 year old sons like watching them with me! Anyhow, I don’t know if you take questions, but putting one here in case you do!: I just replaced my capacitor (thanks to your other awesome video that does a perfect job breaking down how to do that), but now it seems to me that my problem is either the wire connection to the compressor pins, or maybe a totally dead compressor. The fan starts up as it’s supposed to, but the compressor is inactive (no initial compressor “startup attempt” buzzing or anything when the fan starts). Yesterday I took the wires (rubber plug) off the compressor pins, and found that the rubber of the plug had some considerable melting around the plug’s holes to the wire leads. I removed the melted rubber and cleared out those holes to ensure the leads’ connections would be good, and then after I did that and set everything back up and started the AC, the fan turned on (as usual) and I got a big visible spark at the compressor plug. But after that first startup where I got the sparks, for the following startups attempts only the fan started and there was zero activity around compressor startup (as usual). Do you think it’s a dead compressor, or maybe something more simple/less costly to replace (like maybe a new wire/plug)? I don’t own a multimeter, can will buy one if that’s what I need to do to know for sure. Thanks if you do have time to offer an opinion/suggestion!!

[@christopherloeppke4778]

Dude, great video, super clear. Thanks.

[@kingafghan1839]

Your the best HVAC guy

[@valentineradix8735]

You and hvac school are the best...sincerely, tech from Trinidad

[@Smashachu]

Don't forget to short the leads on the capacitor, in older models they don't have a discharge resistor built in and can store a deadly charge.

[@tillerdogg3232]

I wouldn't say deadly

[@boduke2299]

​@@tillerdogg3232 I would

[@MrN75nokia]

I would too

[@ednovak6060]

Thanks for all of the videos

[@BinhLe-qw1eb]

Very informative. Keep up the good work.

[@Orange-Jumpsuit-Time]

Without removing the wires from the compressor pins, I would just verify that each wire running from the compressor pin to the electrical block is good, after verifying good wires, I would check my compressor from that electrical block, no removable of wires, unless one is bad of course, and much easier to check the compressor without fiddling around trying to make a good connection like you were doing. Also my 16 year old Trane unit came with a Compressor Sound Blanket Wrap. I just took the blanket off the other day for testing, and the compressor looks as good as the day it was installed almost two decades ago, not weather beaten like yours.

[@frankshiffer588]

Awesome, exactly what I needed to know. You are the man, Jay.

[@Ridmanjr]

Man I’m sure you just saved me a ton of money today thanks for your videos!

[@dezmengovan7794]

Awesome job you explain everything very well.

[@MegaYounglover]

You’re good technician dude!

[@PBS-nm1uu]

great presentation please keep them coming, love all your videos please do one on icp boards

[@WordofAdviceTV]

Thank you! Videos on ICP boards are a little hard to make since there are sooo many different kinds. It's not like a contactor or a capacitor.. Maybe later on I can try tackling it. Thank you for the suggestion!

[@jamesrooney7689]

thank you for always thinking of our safety

[@mahmoudmizyed5980]

Very good explanation thanks

[@davidmolina8227]

Thanks very good explanation. God bless you

[@topher8634]

I would put one lead on a clean piece of the suction line when checking for short to ground. Putting it on a painted surface can give you a false reading. The suction line is connected to the hermetic shell. Also, if you measure out of limits (OL) it doesn't mean the windings are open. The is an inherent protection called a Klixon embedded in the hermetic windings that will open up if the motor has overheated. This is a common symptom if the run cap is bad and the compressor has been trying to start but is drawing LRA. The protector will open up to keep the windings from burning. You can take a garden hose and cool it down to get the klixon to close again.

[@Progress24.7]

Your checking Volts @ 10:30 . When it should be continuity 🤣 Good video though. Keep up the good work

[@coronavirus1774]

*You’re not Your

[@pastorshandonellis4682]

Great Video Thanks for your time and knowledge. We really Appreciate it.

[@randallcochran9070]

Excellent teaching

[@WordofAdviceTV]

Thank you! :)

[@hassanjamila]

Thank you for this informative tutorial. Everything checks OK on my AC unit. The A coil and filter are clean. Freon pressure is good. Compressor kicks in and cools for about 2 minutes, 55 °F at the register and 72 at the return, then the register temp will gradually climb to about 67 °F and stays that way. What should I check for next?

[@AS-nm9qg]

First of all thank you bro God bless you you are helping a lot of people. Second I have a old unit. If I want put a new compressor, Is it dangerous for my unit?

[@TheHotCollection559]

Best video for this that I have seen

[@nathanmattioli6705]

Thank you for all of the informational videos. It’s helping me to rule out some obvious things. I believe my compressor is bad but it is not shorted to ground and it also has no opens. My ohm readings are all the same. About 9 ohms from C to S, C to R and S to R. Symptoms are it will start and run for 10 minutes and then trip the 50a breaker. One leg is cool and one leg is hot to the touch.

[@davidthomas9444]

Love you videos, very informative!

[@FernandoSanchez-ci8px]

i really like your videos thank you

[@slickerbill5330]

Thankyou very informative !

[@scotjohnson2688]

I have a question if I do all these tests and they pass can a compressor still be bad? Love your Videos they have helped me with my furnace.

[@franciscotejeda1461]

Excellent video , like always n have a good day 😂

[@christyarebalo848]

Thank you for all the videos you do. Our AC was running when we experienced a brown out. Just incase your not familar we lost partial power. Our AC unit made a terrible noise until we were able to shut it off. The next time we went to use the AC we discovered the air coming from the vents inside our home was warm air. We then discovered the fan blades were going around outside nor did we hear it turning on outside as well. That's when I found your videos.......Thank you. We first changed the capacitor, hoping for the best. No luck! We do not have an electrical meter...... but we did push the plunger in manually on the contactor and there is noise coming from the unit but it does not start up nor does the fan start but does move freely when we spin it. We have changed the fuses in the disconnect as well. The brown out is more likely than not the cause of whatever has gone wrong. What would be your best thought on what the brown out most likely would of caused? We currently are in very severe hot weather here in Michigan.......of course!! Thank you for any assistance you can offer!

[@WordofAdviceTV]

Hey Christy! Sorry to hear about the mess that the blowout caused.. Unfortunately without a meter to check voltages with, there is not much I can suggest.. You already replaced the capacitor and the disconnect fuses. I am assuming you tired resetting the AC circuit breaker as well (or checked the fuse if you have a fuse style). I doubt that the power outage damaged both, the compressor and the fan motor.. Although that's a possibility. The only way to know for sure at this point, would be to check stuff with a meter.

[@srobeck77]

You could visually inspect the run of wires going to to your compressor, including taking the cover off at the compressor terminal like he did in the video. Make sure power is off, look for burnt wires. Also your contactor could be bad too. See if that has burn Mark's. Otherwise, just go buy a $15-20 meter.

[@billsmith2212]

On a commercial dishwasher , the contactor on the hot water booster was chattering . 208 Volt , 3 Phase , about 40 Amps . He pressed the button in on the contactor with an insulated screwdriver . A " lightning ⚡ bolt " hit the unit , flash and smoke ! I jumped at least 5 feet . Wet tile floor and S/S dish tables . The manufacturer said some of the heating elements must have been shorted . Mortal terror !

[@adrianhenning1431]

Hello I was confused on how to check the windings would checking winding 2 and 3 then 3 and 2 say the same ohm readings? Like you said at 8:35. I had thought we would read the windings from 1 to 2 then 1 to 3 then 2 to 3 to get the correct ohms?

[@OrlandoLopez-o5w]

😎 CKJ you're keeping a lot families stay cool. Without having to pay the Freon Gypsies. That over charge the compressor. Then 6 to 8 months later thier coming back to replace the capacitor and possibly the contactor. You saved allot of families allot money. Great teaching capabilities. You're living proof their is GOD.

[@MrN75nokia]

Where are the Freon Gypsies

[@noegutierrez6463]

thank u for your effort shearing what u know.. also thank you for the videos you do in Spanish

[@coronavirus1774]

*sharing not shearing

[@Rm-mc8rv]

Good it helps me a lot

[@WordofAdviceTV]

Glad I could help! :) Thanks for commenting!

[@davidregier1463]

Excellent video. No nonsense.

[@WordofAdviceTV]

Thank you! Glad you liked it!

[@richardcascio660]

Excellent presentation as usual. If anyone reads this, I have a question. If you check it at the wires, and everything tests good, you don't need to go to the compressor, is that correct?

[@nsideoutn8439]

Late response but thought I’d do so. Yes, I believe so. But if they are not fine, you would want to check the compressor also to see if it is the wires on the way or the compressor itself. Even though I’m sure by now you got it figured out ha ha

[@valvulak2]

Excellent video, thanks

[@cogcog312]

Excellent. Thanks.

[@TalentNetworked]

Great training. Thanks

[@jaybeliever1479]

Near the end of the video, when you tested the pins to ground, it looks like you had the meter set on Volts, not ohms. Your readings of 0.00 was volts. If it had been ohms, you should have seen OL. Right? But thanks for the very informative videos.

[@aaabeverages7152]

Yes . If its open you get infinity. If its shorted, then it will have impedance resistance of a low value or zero. Open circuit on compressor coil should be 0. Short to ground is less than 1

[@susammachacko4445]

7

[@truthmatters6719]

Great video as always, the only thing I need to ask what's a short to the ground?

[@WordofAdviceTV]

A short to the ground usually refers to a broken, bare, or loose wire that is touching something metal in the unit. In the case of the compressor, shorted to ground would mean that one of the windings inside the compressor is touching metal inside of it which is causing it to short out and trip a breaker.

[@truthmatters6719]

@@WordofAdviceTV thanks man

[@jhguygih]

Very good. My nest is saying is cooling but nothing happened. When i push that manually, it works fine. What could be the issue? How i test the proper cooling wire

[@INTERNA9]

You are my hero! Thanx

[@WordofAdviceTV]

Lol, thank you! Happy to help!

[@aceburns8673]

Have the company come out and pay the service fee. Let them find the problem, thank him and pay him the service fee. Proceed to fix it yourself and if your nice they'll often times walk you through it. Saved big bucks this way

[@GailS.7777]

That does not sound realistic. How would you know what part u need to have on hand while the tech is there and thinking he will wait is wishful thinking. Unless it is something that did not require a new part....

[@AlmarbadiT]

Than you for explaination but What about the LRA ?

[@fernandoescobar692]

Hey a quick question how do you check if your thermo overload is open ?

[@WordofAdviceTV]

The thermal overload is at the common terminal on the compressor. So if it opens, you will not have resistance/continuity between Common to Run winding and Common to Start winding. Long story short, disconnect the 3 wires that come from the compressor and simply check common to either of the two wires. If there is continuity, thermal overload is closed. If not, then it's open.

[@fernandoescobar692]

@@WordofAdviceTV thank you 😊🙏

[@vuonghung3134]

Good job👍👍👍

[@farsali-nw4oo]

Hello sir, if I find a damaged reciprocating compressor, can I replace it with a scroll compressor? Do you advise me on the best way to change the same compressor or change it with a scroll system? Thank you.

[@jaimegonzalez6926]

Good job thanks for your time

[@Mike-we3rb]

Gonna recharge system tomorrow after compressor replacement. They said the compressor is prefilled. Does that mean I don’t have to add any more oil at all? Like does that prefill mean that’s all the systems oil in the compressor or just what the compressor needs itself

[@RobertEmbree-co7nl]

In your video on the compressor wiring, there are two black wires also going to the compressor. Are these for the heater, and if they were not connected what would that effect? I found on my unit th at they were either rotted or cut , and if I reconnect them is there polarity to them?

[@eduardandrade2226]

thank you very much sir for the continue to make more video👍

[@faustosalcedo7873]

👴😃👍👍hey kid keep making video it helping a lot of of do-it-yourself project air conditioning

[@pianduchuance859]

Question three phase compressor should be all the same readings between all whinings

[@samsonandarige396]

hi i like your simplicity of explanation which is good but now the compressor reading i feel little lack of explanation for example you said 1,2 and 3 , which one is 1 which one is 2 and 3 the other one is the big reading is common to what ? if you explain little more clarificationit would more sense a guy like me Thank for your amazing post i love most of your post keep posting

[@carmac1652]

Do you have a video .on freezer compressor relay test ?

[@mits_6131]

Wow! Great explantion of checking compressor pins, not only the wiring. i wish you had you out here on the west coast. Anyone you would recommend in So Cal area in the Inland Empire region.

[@konstantinpukharev7850]

Thank you for sharing

[@jay-c6128]

You're the man

[@ronslaughterandalice1018]

Just a question,,,,, if the compressor is running , couldn’t person tell it’s running by sight and feel ?

[@WordofAdviceTV]

Usually sound alone is enough to tell if it is running or not. The rumbling of a compressor sounds different than the condenser fan.

[@danielsabarle470]

Thanks you bro

[@seanbattles178]

if your compressor is short to ground does that mean another component caused that problem, or do you just change it and your fine?

[@Artlopez105]

On my a c unit I changed the contactor the fan motor and the capisitor it makes a buzzing noise for a second then clicks off nothing happens. I'm not sure what it may be.

[@devinhigdon8165]

and my outside fan continues to shut off and it doesn't sound like my compressor is running should my contact and still be turned what would it still be sucked in even though neither one of them is running

[@georgesierra9038]

Man u r a BEAST! Thanks for your time.

[@WordofAdviceTV]

Lol, thank you!

[@hildyr1052]

Y0u seem honest , where are you located

[@thuantran4804]

My resistance measures 1.2 ohm, 2.1 ohm, and 2.9 ohm. My condenser is currently not running. Capacitor was replaced. Ordering another hard start to see if it can help condenser to start. Does the resistance measurement mean that condenser is broken?

[@DaLeSy.]

What do you do if it IS shorted to ground? Is there a way to fix that?

[@WordofAdviceTV]

Unfortunately there's nothing you can do, the compressor is shot and the best solution is a new air conditioner.

[@1incipitvitanova]

Thanks-you think taking those compressor wires off is hard try putting them back on! My comp is bad, just got a quote of $3,200 to replace, w/ no guarantee of course, that something else could go wrong soon after on my 11+ year old 2.5 system. And R-22 too!

[@srobeck77]

R22 is a system breaker if u have a leak. But I've heard good results with NU22 as a replacement.

[@flyme-z7b]

When you power up the unit using the contactor plunger does the furnace itself have be in some particular setting or mode? In my case I am in heat mode (because it's winter) and I want to quickly bypass and troubleshoot different parts of the system. Using the plunger would be convenient, just want to do it right.

[@freedom0164]

Great video!!!

[@canioturlione7639]

What is the Compressor Min outdoor Temperature be set at my unit could take up to-15 and also Aux heat Max outdoor temperature. When its - 4 and up won't kick in unit outside i must have setting wrong

[@mytexasdays1526]

I can't remove the wiring harness from the compressor. I tugged the black cover as hard as I could but it's not coming off. Why is it that hard to get off? It's a 20+ yr old r22 3.5 ton Copeland.

[@okegs4real]

Are compressors interchangeable? My condenser is ssx140421cb with compressor ZP31K5E-PFV-830 which has gone bad. I bought part ZP42K5E-PFV-800 as a replacement. Will this fit without any issues or cause damage?

[@DaLeSy.]

Question. I tested it the way you showed in resistance (the horse shoe) using alligator clips on my meter for better contact. The first reading gave me these numbers: 4.1, 1.3, and 3.5. And the smallest two numbers added up doesn't equal the highest number. The highest number was 4.1, and the other two added together would be 4.8. But you did say it could be one or two off. But I don't know if you are talking about the number before the decimal point, or the number after. Does that sound good or bad? I tested it a second time, and the second time I got these numbers: 4.5, 1.8, and again 3.5. And 1.8 + 3.5 = 5.3, so this time the number before the decimal point is 2 higher. Would that be good or bad? Also I am noticing that the black wire looks a bit burnt on the end, and there is a bit of rust on one terminal and one or two connectors. When I did the other test to see if it was shorted to ground, I am not sure what you have your meter set to for that test. It doesn't look like it is on resistance. It looks like AC volts. When I did that test in resistance or ohms I got the O/L for all three. But when I changed it to AC Volts. I got 30. mv for each one when one of the wires was connected to the pipe. O/L when touching the compressor where I scratched it. (Btw, I already tested the capacitor, contactor, and fan motor following your videos - they all tested good. It won't kick on, nor does the fan come on, but it makes a light buzzing sound that I could hear that some people wouldn't even notice. One time before that there was a popping sound when I turned it on. And the capacitor was leaking so I replaced it.)

[@ClayMatthewsJr52]

Good morning how do I check the compressor. Do I check it from common to start then common to run the start to run also I have one that's locked up