Mr Gray i m 30 yrs in the AC Trade but i have a lot of Respect for your Teachings and when i get stuck i go to your channel to learn more about it. Also i watch when you have the show talking to the 2 other guys sharing Field exp....i like Guys like Israel, ZACK, The hvac guy in Georgia i think Curtis is his name, i like experience guys in general always helping guys like me....blessings to u n fam
So helpful! Most other videos simply show the presenter clamping some "unknown wire" (he seems to just assume you know which one to measure on), or -- worse - the meter is already surrounding the wire and ready to take a reading (without ever having shown you how to locate the correct wire. This was PERFECT!.
Thank you for your knowledge You make my troubleshooting class for furnace and AC a lot easier and very enjoyable seeing what I learn at home and getting the results i want in school
grayfurnaceman It will always be the highest amp draw on reading and always connected to the contactor helped me a lot fixed 2 over charged units today
I know on DC systems it doesn't matter which wire you choose to test AMPs, but I've wondering about in an AC system- thanks for finally giving me an answer!!
thanks! Im trying to chase down a "your compressor is going out" because the amp draw is to high situation from a service tech but he was talking about the compressor but only testing the current on incoming (main) power wires - adding them together to get a total that he says is to high so what I am looking at is the compressor wire only???? is there a percentage or rough guess of max (rating plate) value that tells you its to high??? mine is a Trans 5 ton 13 seer - I want to make sure this is not getting ready to crap out before 100 + summer really hits here in texas giving me 13k estimate for new system so Id really like to be sure first the unit cools well. thanks for the videos they really help!
Dear Mr. Gray, you have SO Much Knowledge and So Much Talent and we love the way you share it with all of your subs and just folks that stumble on to your videos. Please consider A-Team Adams invitation for the HVAC Overtime Stream... Thank you for all that you do for us and Very Best Regards to You and Your Family!
I checked the max amps and amp draw right at the main panel for the double pole circuit breaker that supplies the AC. . Each leg had a max draw of -80 amps (81 on one and 77 on the other) on start up and ran at 17.5 amps steady state. Used a Fluke 87V in high res mode. The RLA is 23.7 amps and the LRA is 129.0 amp per the specs on the unit. It’s a 4 ton (48,200 BTU) unit. I do have a 5-2-1 kit on it as well. I’ve never tried it but I don’t think my 7500 W peak generator will start this unit.
@@grayfurnaceman - guess it won’t hurt to try? It’ll just trip the generator breaker. My panel is a 30 amp double pole and it doesn’t trip. All comes down to how much time that 80 amp spike goes on for… Ttanks
However keep in mind that if you get a no ac and your heat pump breaker is tripped, there is a good chance there’s a problem at the disconnect, contactor, or compressor itself, if you unplug the molex of the compressor and turn the breaker back on and it doesn’t trip, your compressor is done. Your compressor pulls the most amperage on the circuit because the outdoor fan does not
Mister furnace man, you made a great video. Tell me, is it better to check the amp draw at the contactor or right next to the compressor where the wires enter the compressor?
Goodman package unit 3.5 ton. Liquid line sweating amp draw is 17. Diagram says 19amp. Conpressor makes loud sound on start up? Stuck on this. Any ideas?
If there is a delay when the compressor starts, the compressor may be failing or the capacitor is failing, Check the capacitor strength. If ok, you may need a hard start kit. This could extend the compressor life but only marginally. GFM
Hi, I have a york residential ac about 3 years old. Was working fine until now. The static pressure equalizes about 150psi. On a call for cooling the low side goes into a vacuum and drops to about 10psi while the high side goes up to about 200psi. The low pressure sensor trips and compressor stops for a few second. The unit then equalizes about 150psi again. BUT, when it starts again this time compressor really loud noise and low and high pressure barely moved. I do see oil around the brazing point at suction service valves. Can this be low charge or bad compressor? Compressor windings checked ok. Thank you for your help.
@@grayfurnaceman Was talking to a "big time" nyc commercial hvac guy yesterday. "The new systems - they have to run at higher temperatures and pressures. The equipment is new and it's always breaking down" Ohhhhh... You don't say.... And I'm thinking "thank you c--- s-----s of that stupid Montreal Protocol." PS: these stupid blends we have to live with - post ozone quackery: As per your video about Blends, they fractionate - ok. That means: if there's a leak, the whole f------ refrigerant charge has to be replaced, right? B/c fractionation means one of the gases leaks out more than the others, so the ratios are screwed up, and you have to start over with a new charge, correct? (Am walking the line between good hvac student and Disgusted American.) ++++++++ As a refresher, here is The Ozone Scam: ruclips.net/video/9Szs-treHwQ/видео.html It's not perfect, but it's a good indicator of the stupid country EPA and DOE have turned us into.
There is no set rule here. And draw varies with voltage, load, charge level and ambient temp. If the draw is 1/2 or lower of the RLA with voltage within 90% of the rating plate, I would be concerned. GFM
What happens to the amperage draw if the AC is low on refrigerant ? Also what happens to the power consumption if the pressure of the refrigerant is getting lower ?
If the ac is low on frion you can expect the compressor to have more of an amp draw because it's trying its best to work at full capacity while it's missing the required refrigerant amount
Today I have a strange low contractor problem. The AC condenser unit runs about 5 to 10 minutes, then stopped, but indoor motor still running. After about another 5 to 10 minutes, the condenser unit started to run again. I checked the low voltage at the condenser contactor, I had 24v power. When I put the low wires back to coil sides, the contactor wouldn’t pull in. I checked several new contactors, including single pole, 2 poles, 3 poles, they all had the same problem: when I first put low wires at the contactor coil sides, contactors pulled in, then I disconnected one wire, then put it back, the contactor then wouldn’t pull in. The low voltage power is there. Any ideas? Thank you
Make sure your thermostat isn't reaching your set temp. Could be that. Could also be low pressure switch opening from low charge just as grayfurnaceman stated. Could be high pressure switch opening as well if you don't adequate airflow, like a dirty filter for example. Your contactor situation is a different problem. Contactor sounds good but there could be a delay board or one of those PG&E delay boxes. Or one of those switches could still be open. A lot of different possibilities.
@@grayfurnaceman which means your leaking and if the fittings are tight the leak might be terminal.. tell me another way a leak can be fixed though as you are the master.
Why not check it both before and after the contactor to see the health of the contactor. I suppose if it's different, then the contactor is causing extra amperage and possible needs to be replaced if the connection is pitted.
@@mtbbiker6401 The best way to test contactor resistance is to check voltage drop across the contacts. Place your voltmeter probes across the contacts. The result is the voltage drop. Over .2 volt means the resistance is excessive. GFM
@@grayfurnaceman I finally got around to testing this. I have a very similar 5 Ton Trane Heat Pump unit (26 RLA) My amps on the Common (black/blue wire) is 21.5A both before and after the contactor (105 degree ambient temp outside). The Red Run wire was getting a different reading. Before the contactor I'm getting 21A but after (compressor side) it's only 16A. Is this because the capacitor is also connected to that side of the double pole contactor? Also the contactor is only 1 year old. When I installed it I didn't see a side listed as L or T, so does it matter the orientation of the install? The contactor is a double pole and it appears symmetrical with no L1,L2,T1,T2 markings. Thanks!
Maybe someone can help me. I called Yes air conditioning in Vegas for my hvac Lennox brand to be tuned up for the summer time. The tech said my amps for my a.c. compressor is too high,the panel has 17.9,and the tech read on his multi meter it's at 17.1, he said it's way too high and that my a.c. won't make it in the summer,and that I need a new one. He changed the compacitor and the a.c. compressor went to a 15 or 16 amp. He said it will be ok for now n it's just a band aid,but it won't hold up. Idk if they are trying to sell me a brand new a.c. or what. Any thoughts
Gray Man: Was this a 120 or 240 volt unit? Need the info to compute the watts and thereby the cost per hour to run. 8 cents per KWh for power. Thank ou.
@@mitchdenner9743 About 0.13 - are you sure you are including both transmission and production costs? Usually listed separately.. it is what happened when a guy in PA told me he paid 0.06 - I'm in MD
@@Swoliosis1 thats the price per kwh not included transmission. Teds comment was the price he paid for generation only. You don't include transmission when comparing price per kwh. Jcp&l's delivery charge is 3 cents x how ever many kwh you use per month. My monthly bill in a 1800 sqft house is between 50 and 90 dollars a month. I actually shop around my rates every year or two. Jcp&l's rate per kwh is actually 10 cents, but i use a green energy supplier that gives me a lower rate. I've had prices as low as 7 cents in the past. Its a win win, not only do i get a lower rate, its clean energy generation. So its worth my time to shop around every year or two.
@@grayfurnaceman makes sence. It was a little cool outside. Customer stated that the compressor shuts off after 15 minutes on a hot day. And starts up again after a while.
@@ar420420 If the compressor shuts down but the fan stays on, it is probably going out on internal overload. Many possible reasons why. Low charge, non condensibles in the system, overcharge, capacitor failure, etc. GFM
9.5 amps at what voltage? I'm guessing you're an America so you don't know that every country has different voltage so I'm not gonna make fun of you or insult you or say anything against your ignorance. But can you please tell me how many volts did you measure the amps at? 🤔
This video is about how the check amp draw of the compressor. The voltage is not part of the point here. Its about finding the common wire so you can be checking the right wire. GFM
@@grayfurnaceman you didn't even showed that in the video. You just showed a bunch of wires and selected 2 of them without explaining why you chose them. Selecting the correct voltage is the most important part because amps mean nothing without it. The real power consumption can only be measured in Watts. I hope you understand what I'm saying
Mr Gray i m 30 yrs in the AC Trade but i have a lot of Respect for your Teachings and when i get stuck i go to your channel to learn more about it. Also i watch when you have the show talking to the 2 other guys sharing Field exp....i like Guys like Israel, ZACK, The hvac guy in Georgia i think Curtis is his name, i like experience guys in general always helping guys like me....blessings to u n fam
Thank you so much 🙏🏼man I’m a 19 yr old service technician and this is really helpful for diagnosing compressors leading towards failure
Thanks gray I really appreciate what you’re doing. God bless you and your family
Welcome
GFM
So helpful! Most other videos simply show the presenter clamping some "unknown wire" (he seems to just assume you know which one to measure on), or -- worse - the meter is already surrounding the wire and ready to take a reading (without ever having shown you how to locate the correct wire. This was PERFECT!.
Thank you for your knowledge You make my troubleshooting class for furnace and AC a lot easier and very enjoyable seeing what I learn at home and getting the results i want in school
Glad it has helped.
GFM
grayfurnaceman It will always be the highest amp draw on reading and always connected to the contactor helped me a lot fixed 2 over charged units today
I know on DC systems it doesn't matter which wire you choose to test AMPs, but I've wondering about in an AC system- thanks for finally giving me an answer!!
Great video! Short and simple but very helpful. Keep making videos. Thank you very much
Welcome
GFM
Good video man very simple task many MTs can’t do correctly
Thanks for all your videos help me a lot have a wonderful day
Welcome
GFM
Thanks alot. Very helpful and straight to the point
Great video
thanks! Im trying to chase down a "your compressor is going out" because the amp draw is to high situation from a service tech but he was talking about the compressor but only testing the current on incoming (main) power wires - adding them together to get a total that he says is to high so what I am looking at is the compressor wire only???? is there a percentage or rough guess of max (rating plate) value that tells you its to high??? mine is a Trans 5 ton 13 seer - I want to make sure this is not getting ready to crap out before 100 + summer really hits here in texas giving me 13k estimate for new system so Id really like to be sure first the unit cools well. thanks for the videos they really help!
Excellent Video, thanks!
Great video GFM 👍
Great video today!
Love the hawk at the beginning : )
Thanks! Very nice explanation
Dear Mr. Gray, you have SO Much Knowledge and So Much Talent and we love the way you share it with all of your subs and just folks that stumble on to your videos. Please consider A-Team Adams invitation for the HVAC Overtime Stream... Thank you for all that you do for us and Very Best Regards to You and Your Family!
Great Video. How do I know when compressor need to add Hard start capacitor or hard start kit ? Could you make video about it. Thank you.
I can and will be doing a video on hard start for compressors and when it mis necessary.
GFM
Now that's a good video!!!!!
I checked the max amps and amp draw right at the main panel for the double pole circuit breaker that supplies the AC. . Each leg had a max draw of -80 amps (81 on one and 77 on the other) on start up and ran at 17.5 amps steady state. Used a Fluke 87V in high res mode. The RLA is 23.7 amps and the LRA is 129.0 amp per the specs on the unit. It’s a 4 ton (48,200 BTU) unit. I do have a 5-2-1 kit on it as well. I’ve never tried it but I don’t think my 7500 W peak generator will start this unit.
It may if there is no other load.
GFM
@@grayfurnaceman - guess it won’t hurt to try? It’ll just trip the generator breaker. My panel is a 30 amp double pole and it doesn’t trip. All comes down to how much time that 80 amp spike goes on for… Ttanks
Another good video!! 👍🏾👍🏾
How would we determine amp draw on a three phase compressor? Great vid!
Clamp any one of the 3 wires. That is your amp draw.
GFM
@@grayfurnaceman Thank you sir!
And also common for the fan motor?
Looking for info on checking inrush amps. Do you have a video or info you can share?
Thanks.
Thanks for the info!
I just checked it at the breaker panel. Should be same result, right?
Always.. Thank you
Nice video. Thank you. I just want to make sure I understand. You measured the running amps of this compressor, not the inrush. Correct? Thanks.
Yes
GFM
However keep in mind that if you get a no ac and your heat pump breaker is tripped, there is a good chance there’s a problem at the disconnect, contactor, or compressor itself, if you unplug the molex of the compressor and turn the breaker back on and it doesn’t trip, your compressor is done. Your compressor pulls the most amperage on the circuit because the outdoor fan does not
Another quick question: can excessive and continued amp draw destroy a capacitor prematurely?
I have never seen it happen.
GFM
Is there anyway to lower the amps to use less power?
You can try cleaning the outdoor coil. There is nothing more that you can do that is effective.
GFM
Mister furnace man, you made a great video. Tell me, is it better to check the amp draw at the contactor or right next to the compressor where the wires enter the compressor?
You can check at the contactor but you must be downstream of the contactor and clamping only the compressor wire.
GFM
tank you vic video
Goodman package unit 3.5 ton. Liquid line sweating amp draw is 17. Diagram says 19amp. Conpressor makes loud sound on start up? Stuck on this. Any ideas?
If there is a delay when the compressor starts, the compressor may be failing or the capacitor is failing, Check the capacitor strength. If ok, you may need a hard start kit. This could extend the compressor life but only marginally.
GFM
Hi, I have a york residential ac about 3 years old. Was working fine until now. The static pressure equalizes about 150psi. On a call for cooling the low side goes into a vacuum and drops to about 10psi while the high side goes up to about 200psi. The low pressure sensor trips and compressor stops for a few second. The unit then equalizes about 150psi again. BUT, when it starts again this time compressor really loud noise and low and high pressure barely moved. I do see oil around the brazing point at suction service valves. Can this be low charge or bad compressor? Compressor windings checked ok. Thank you for your help.
Low charge. Soap bubbles on the oily part of the service valves will tell if you have a leak there. They are very small, so look close.
GFM
Thank you sir.
Thank you!
Welcome (no complaint about new vs old?) lol
GFM
@@grayfurnaceman
Was talking to a "big time" nyc commercial hvac guy yesterday.
"The new systems - they have to run at higher temperatures and pressures. The equipment is new and it's always breaking down" Ohhhhh... You don't say....
And I'm thinking "thank you c--- s-----s of that stupid Montreal Protocol."
PS: these stupid blends we have to live with - post ozone quackery: As per your video about Blends, they fractionate - ok. That means: if there's a leak, the whole f------ refrigerant charge has to be replaced, right? B/c fractionation means one of the gases leaks out more than the others, so the ratios are screwed up, and you have to start over with a new charge, correct? (Am walking the line between good hvac student and Disgusted American.)
++++++++
As a refresher, here is The Ozone Scam:
ruclips.net/video/9Szs-treHwQ/видео.html
It's not perfect, but it's a good indicator of the stupid country EPA and DOE have turned us into.
What is considered low amp draw and how do determine if the amps are to low?
There is no set rule here. And draw varies with voltage, load, charge level and ambient temp.
If the draw is 1/2 or lower of the RLA with voltage within 90% of the rating plate, I would be concerned.
GFM
Gold
What happens to the amperage draw if the AC is low on refrigerant ?
Also what happens to the power consumption if the pressure of the refrigerant is getting lower ?
If the ac is low on frion you can expect the compressor to have more of an amp draw because it's trying its best to work at full capacity while it's missing the required refrigerant amount
Today I have a strange low contractor problem. The AC condenser unit runs about 5 to 10 minutes, then stopped, but indoor motor still running. After about another 5 to 10 minutes, the condenser unit started to run again. I checked the low voltage at the condenser contactor, I had 24v power. When I put the low wires back to coil sides, the contactor wouldn’t pull in. I checked several new contactors, including single pole, 2 poles, 3 poles, they all had the same problem: when I first put low wires at the contactor coil sides, contactors pulled in, then I disconnected one wire, then put it back, the contactor then wouldn’t pull in. The low voltage power is there. Any ideas? Thank you
With the info you have given, I would think you have a low pressure switch opening, probably from low charge in the unit.
GFM
Apprentice - volt meter training time
Check the fuse in the disconnect or the double pole breaker at the panel
Make sure your thermostat isn't reaching your set temp. Could be that. Could also be low pressure switch opening from low charge just as grayfurnaceman stated. Could be high pressure switch opening as well if you don't adequate airflow, like a dirty filter for example. Your contactor situation is a different problem. Contactor sounds good but there could be a delay board or one of those PG&E delay boxes. Or one of those switches could still be open. A lot of different possibilities.
@@grayfurnaceman which means your leaking and if the fittings are tight the leak might be terminal.. tell me another way a leak can be fixed though as you are the master.
Why not check it both before and after the contactor to see the health of the contactor. I suppose if it's different, then the contactor is causing extra amperage and possible needs to be replaced if the connection is pitted.
If there is an appreciable drop in amperage, the contactor would be burned up. Contactors are not loads and cannot dissipate heat.
GFM
@@grayfurnaceman Thanks. So would it be better to check the contactor using ohm resistance?
@@mtbbiker6401 The best way to test contactor resistance is to check voltage drop across the contacts. Place your voltmeter probes across the contacts. The result is the voltage drop. Over .2 volt means the resistance is excessive.
GFM
@@grayfurnaceman Great advice. I will test.
@@grayfurnaceman I finally got around to testing this. I have a very similar 5 Ton Trane Heat Pump unit (26 RLA) My amps on the Common (black/blue wire) is 21.5A both before and after the contactor (105 degree ambient temp outside). The Red Run wire was getting a different reading. Before the contactor I'm getting 21A but after (compressor side) it's only 16A. Is this because the capacitor is also connected to that side of the double pole contactor? Also the contactor is only 1 year old. When I installed it I didn't see a side listed as L or T, so does it matter the orientation of the install? The contactor is a double pole and it appears symmetrical with no L1,L2,T1,T2 markings. Thanks!
Maybe someone can help me. I called Yes air conditioning in Vegas for my hvac Lennox brand to be tuned up for the summer time. The tech said my amps for my a.c. compressor is too high,the panel has 17.9,and the tech read on his multi meter it's at 17.1, he said it's way too high and that my a.c. won't make it in the summer,and that I need a new one. He changed the compacitor and the a.c. compressor went to a 15 or 16 amp. He said it will be ok for now n it's just a band aid,but it won't hold up. Idk if they are trying to sell me a brand new a.c. or what. Any thoughts
There is nothing in the information you gave that would indicate to me that your unit is failing.
GFM
@@grayfurnaceman wow thank you for the reply back,idk if the tech is trying to sell me a brand new a.c. n wanted a sale.
Gray Man: Was this a 120 or 240 volt unit? Need the info to compute the watts
and thereby the cost per hour to run. 8 cents per KWh for power. Thank ou.
Wow, where are you paying only 8 cents?
I pay 8.89 cents also in nj.
@@Swoliosis1 where are you at and what do you pay?
@@mitchdenner9743 About 0.13 - are you sure you are including both transmission and production costs? Usually listed separately.. it is what happened when a guy in PA told me he paid 0.06 - I'm in MD
@@Swoliosis1 thats the price per kwh not included transmission. Teds comment was the price he paid for generation only. You don't include transmission when comparing price per kwh. Jcp&l's delivery charge is 3 cents x how ever many kwh you use per month. My monthly bill in a 1800 sqft house is between 50 and 90 dollars a month. I actually shop around my rates every year or two. Jcp&l's rate per kwh is actually 10 cents, but i use a green energy supplier that gives me a lower rate. I've had prices as low as 7 cents in the past. Its a win win, not only do i get a lower rate, its clean energy generation. So its worth my time to shop around every year or two.
I did not see where you found the info on amp specs for the compressor. You talked about it as if we already knew what you were looking at
All units have a model plate, generally on the outside of the unit. The max amp draw of the compressor will be noted there.
GFM
@@grayfurnaceman I don't know how I am missing it. I have been looking over the all the data on the unit
@@waterssolar5025 Some units have it on the electrical panel underneath a cover.
GFM
RLA doesn't mean running load amps
Cant you just check the one from the capacitor
Rla at 13 amp draw is at 7. What’s that mean?
It means the compressor is under light load.
GFM
@@grayfurnaceman makes sence. It was a little cool outside. Customer stated that the compressor shuts off after 15 minutes on a hot day. And starts up again after a while.
@@ar420420 If the compressor shuts down but the fan stays on, it is probably going out on internal overload. Many possible reasons why. Low charge, non condensibles in the system, overcharge, capacitor failure, etc.
GFM
Not to hard to get to run Its right there in front of red start and next to blue-black common
9.5 amps at what voltage? I'm guessing you're an America so you don't know that every country has different voltage so I'm not gonna make fun of you or insult you or say anything against your ignorance. But can you please tell me how many volts did you measure the amps at? 🤔
This video is about how the check amp draw of the compressor. The voltage is not part of the point here.
Its about finding the common wire so you can be checking the right wire.
GFM
@@grayfurnaceman you didn't even showed that in the video. You just showed a bunch of wires and selected 2 of them without explaining why you chose them.
Selecting the correct voltage is the most important part because amps mean nothing without it. The real power consumption can only be measured in Watts. I hope you understand what I'm saying
@@fsalhin99Wow 😂
@@fsalhin99He already told you that thus video is about checking AMP DRAW!!!
Thanks for refresh