How to diagnose a locked rotor compressor
HTML-код
- Опубликовано: 19 ноя 2024
- This one covers determining if a compressor has failed due to locked rotor.
This video is part of the heating and cooling series of training videos made to accompany my websites: www.graycoolingman.com and www.grayfurnaceman.com to pass on what I have learned in many years of service and repair. If you have suggestions or comments they are welcome.
If you are a homeowner looking to repair your own appliance, understand that the voltages can be lethal, the fuels are highly flammable and high pressures are used. Know your limits.
My son is learning to be a tech and i want to say you are the best at teaching him!!!!
thank you
Best hvac instructor ever. Thank you!
I should have been more explicit. Yes. If the compressor locks, it must be replaced. You can try a hard start, but even if it works, the compressor will have a limited life. The locked rotor is the best case if you must have a failure. A burnout is the worst, as the system is then contaminated with smoke and burned winding insulation. Thanks for the heads up.
GFM
Great info.
Thanks a lot. I didn’t even know what the LRA was. So if I see that it’s possible to put a hard start kit on give it some more time before they replace? I’m now very concerned about what you said with the system being contaminated from burnt motor. I’ve replaced a few compressors(I just went from install to tech in March). I did replace the refrigerant and filter dryer when doing that, but could I’ve messed up the system for those customers if the motor was burnt?
@@jacobbell1934 Hard starts are a short term fix that could be useful in some cases.
If you get a burned smell from the refrigerant in the system, I would recommend installing both a liquid line and suction line filter with replacement of the driers after a few days operation.
GFM
You helped me out so much! I changed my capacitor but it would not start, only made a buzzing noise. I started it manually pushing the button that you pushed and it cranked up!!!! Thank you Sir and GodBless
Great job explaining the LRA and how the Comp is locked up and why.
Thanks for the support.
GFM
Unit running A OK, came back to find out lose low voltage connection @ A/H.unit. Thanks you for sharing your valuable time, resources and knowledge to help us new tech. Learn st new everyday out the field.
On a call right now & with forgot how to check just windings without ohming fan motor you a a great guy , going try out a jump cap hope it works
Good video.... I am looking forward to your capacitor trouble shooting video, I knew a guy who replaced a compressor thinking it was bad and when he replaced it, it still kicked off on internal overloads. He then later figured out that it was a bad run capacitor and he regrets ever replacing the compressor because it was just a bad run cap the whole time.
LRA (Locked Rotor Amps) is an electrical measurement of current for starting a motor, compressor, or any inductive load. It is referred to as in-rush. It is when the rotor starts from a stopped position and draws between 5 to 7 times more amps to start the load when compared to RLA. Also, in order to properly measure in-rush, you need a clamp meter that can read in-rush. In-rush occurs within the 1st-2, to 3 cycles of the 60hz frequency. Only specialized meters can read that quickly and they range from $500 on up.
Harbor freight CM1000a clamp meter measures in rush for 100 bucks. Not the kind of meter you can brag about to your friends but still better than nothing.
Great explanation. Straightforward and to the point.
LRA means locked rotor amps. This is the amp draw when the rotor of the compressor is stuck. RLA means run load amps. This is the maximum amp draw while the compressor is operating.
GFM
What's the meaning FLA
Compressors start very quickly. Locked rotor amps is only present for a fraction of second. If you push in the contactor and it does not start, you have 3 to 5 seconds before the overload goes off so a short try will tell if it is going to run. Hope this helps.
GFM
I digress and agree with the information in the video my comments were only for open forum discussion not a direct criticism of the video or it's instructional value it was a great video and the quickest way to trouble shoot a compression problem
Thanks for the thoughts.
GFM
All the compressor manufacturers will recommend minimum oil quantity that should always remain inside the compressor for lubrication.If your refrigeration line circuit is larger,then the oil takes more time to get back to the compressor.In that case,we must charge more oil (10% of total quantity).
Try the above,definitely the compressor failure problem will be solved.
9years later great video !
For LOCKED COMPRESSOR ROTOR - We have 3 different scenario.
1.Rotor Locked,but winding is good and no short to ground.
2.Rotor Locked-winding failure,but no short to ground.
3.Rotor Locked-winding failure and short to ground.
Major reason for all the above symptom is possibly Low Compressor Lubricating oil inside the compressor.Just flush out the system and collect the oil from the ref.lines and also measure oil remaining inside the compressor.Sum up both collected quantity and compare it with compressor total oil quantity.
Hi boss thanx for information
The replacement of the evap indicates there was leak in the system. That can cause overheat of the compressor. Also, the outdoor fan replacement means the fan was not running which can also cause overheat. I can't say about a company's integrity. Sometimes when major repairs are done, other failures pile up.
GFM
Thanks for the support.
GFM
That's the defrost board. This is a heat pump. The light is a diagnostic light. Hope this helps.
GFM
There is no backwards compatible R-410A unit to R-22. It can be done but will not work without a change in expansion device and no manufacturer that I know of recommends it.
GFM
Great explanation GFM you are the best!!!!!!
Thanks for the video. Shouldn't the compressor draw LRA for a few seconds anyway? Could you push in the contactor and determine if the amps drop off, or were you saying too long would trip the overload
I like the way you explained that Keep the good vids coming . Thanks for sharing
Straightforward as always thank you so much
I actually got a locked AC compressor to run after hitting the top of it with a rubber mallet. Three years later it still running....
Agreed.This had happen to me once.But very rare.For 3-Ph compressors,we can release the rotor lock by reverse rotation.
Anand Gbk how can on reverse the rotor rotation?
gabriel peter by swaping any to phases going to the compressor.
I might need to learn what the hell you mean.
By switching the start and run leads going to the compressor you can reverse the direction of the compressor thus freeing the locked rotor. Then switch the leads back to normal and try it again. Only for three phase motors!!
Not exactly how I would have done it, but to each their own. Voltage and wiring to compressor to verify would be a last "to be sure" check.
Now- why did the compressor go to lock rotor?
Ohm the windings to see if one winding may be weak.
Was it due to a dirty indoor coil, blower motor cycling or quitting, system overcharged, crank heater failure, voltage problem, restriction in metering device and loss of oil in compressor- etc.
Good video.
Thanks for the thoughts.
GFM
you must of been new when you wrote this comment. dirty indoor coils not going to lock your rotor up, crank case heater failure could cause valve issues but i highly doubt rotor locking, system overcharge not going to lock your rotor and restricted metering device is not locking the rotor, usualy the causes for your rotor locking is an electrical issue whether bad capacitor or potential relay, low voltage, phase loss or simply motor seizing
Tanks you for this tutorial. It's vert nice. What's différence LRA and RLA?
For the most part you are very good a helping us new guys learn how to do thing right but. Ok Locked rotor compressor meads new compressor?
Yes
Excellent demo!
Hello gfm.. have you had an rtu unit that doesn't have voltage in one leg from the box. I replaced the switch box fuse, and the fuse box inside. Nothing no power?? So compressor doesn't come on
Its hard to stop a Trane... :) Thanks for another informative video.
That don't sound like a locked rotor. Sounds like burned windings. Also sounds like money.
GFM
Great video - Thank you. Please make more videos
I do at least one a week.
GFM
hey the uei voltmeter you use is there a video that you have to learn how to use it or a website you can direct me too i have the very same one but is not to good in it yet
Another great video, thanks GFM
Digital flash on the 419' is because the power was reset, has a built in time delay, you do not use those 419s, very expensive, used for refrigeration, thermal disc, or fossil fuel kit, way cheaper
My compressor exploded the other day. Green liquid came out of it with horrible odor. Everything started well but the compressor took 10-15 mins to start. Now, I'm here in Texas with no AC. Sucks
I’ve got a 10 year old Rheem heat pump that as soon as it gets the call for heat or cool, it pops one of the two fuses in the disconnect or trips the breaker. The outdoor fan gets barely enough power to turn the blades a 1/4 turn. I replaced the contractor and same problems. I take the outdoor fan motor out of the loop completely and same problem. Ohm out compressor at its plug and it’s fine (OL).
You have a dead short to ground. Baring a wire contacting ground, I am betting the compressor is shorted to ground. Unplug the compressor wires and check again.
GFM
@@grayfurnaceman - That was the very first thing I did. Run, start and common pins on compressor to ground and all (OL). In fact I rechecked it yesterday. I have checked every single wire in the outdoor unit thoroughly.
@@jameswestii454 Remove and isolate all wires to the compressor. Then turn on the power. Ohmmeters do not always tell the tale.
GFM
hello I have a Comfortmaker 10 that when you turn it on the fan may come on but the compressor does not come on my local AC guy says that the compressor is needs to be replaced, does it?
Hi, how to diagnose an inverter compressor if it's locked or not? Thanks sir
did you get this old trane xe1000 heat pump fixed or a new unit just wondering
Good Explanation dude thanks ❤️
Welcome
GFM
It was replaced due to the owner wanting current efficiency equipment.
GFM
I have a package ac unit that recently had a condenser fan motor replacement done on it and the original condenser fan motor was a 1/8 horsepower 1100RPM motor and the one my repairman installed is a 1/2 horsepower 1075RPM motor and so far it's been working good so far do you think that over time it will cause damage because the unit itself is à 20 year old unit and he couldn't get the oem part because they don't make the same brand as what motor originally came in the unit
It should not cause any damage, in fact it may reduce the head pressure a little.
GFM
@@grayfurnaceman that is a good thing
This one managed to get stopped. It is a good product line though.
GFM
Thanks GFM. What can go wrong , if LRA is below data name plate, compressor ohm check out is good, dual cap is good,230v voltage present at the comp terminal, any advice what I am missing. Thank and love your video!
First, what was the original problem? Does the compressor not run? Does it run and not pump?
GFM
great video
Have you seen a locked rotor compressor trip the breaker? I checked the windings on the compressor and they weren't grounded and the compressor wouldn't start. The capacitor was good as well.
Yes. Sometimes the overload opens, sometimes a fuse or breaker kicks off.
GFM
Hi GFM.I live in the Caribbean and we have a little resort and maintain all my own equipment as there is no one here to do so.I was in the HVAC business years ago so still pretty knowledgeable .Yesterday our walk in Freezer compressor kept starting and stopping after 15 seconds.Pressures are good condenser and evap coils clean fairly new compressor .I noticed the compressor common was drawing 13 amps and the Run was drawing 2 amps then all of a sudden it started working fine again any thoughts ...Thanks and great videos.Very helpful
Are you sure the compressor was starting and changing the pressures? I am thinking you had a locked rotor. Also, the amp draw of run should be higher than you read.
GFM
What would the standing pressures be if you hook up your gauges to it?
The pressures should correspond to the ambient temperature for a saturated vessel. Hope this helps.
GFM
The compressor was reading high suction pressure and low head pressure. The compressor sounded like it wanted to start, but then it would just turn back off. I checked the capacitor it was good, I checked the compressor windings also and they were good. Do you think I should install a Hard Start?
SombraLocs if a hard start does not work take a piece of wood and put it on the compressor and hit it with a hammer, Might sound stupid but i have unlocked a bunch of them that way. Then the hard start will give it enough boost to start without locking up.
+Jerry Mullins thank you! It's 1am and this compressor has been stuck all day on the hottest day in history in San Diego. Couldn't sleep it's so hot tonight so I was hunting for answers. Good ol crack in the ass on that compressor with my rubber Mallet and it started right up. It's been locking up on and off for a couple years now. Usually it will start up if I shut it down for a day or so. I skipped all the trouble shooting and went straight for the slap. I did pay an AC tech to come check it out but by the time he got here it started fine. He topped off the gas, checked the capacity and couldn't find anything wrong. I guess this thing is on the way out. Glad it's cooling my room down tonight.
+grayfurnaceman Pressures on a "Locked Rotor" are static... 150 on both gauges... Are you paying attn?
cool thanks again only one that question
to that effect
where is the C from the compressor
connection on the contactor
on t1 or t2 let me know
because in different ways
connect in t1 on other ways
the C connect on t2 is difficult understand
I need to know there is the right
thanks
Depends on the manufacturer. C is often not disconnected by the contactor. There is no right or wrong way.
GFM
I have a goodman unit with a comfortnet thermastat that says locked rotor.
My ac man was not sure what was wrong. We flipped the breaker off and let it rest for 30 minutes and then flipped the breaker back on. The unit ran fine after that for about a month. Then the locked rotor screen came back on and so I flipped the breaker on and off and it worked for about a week and then locked rotor screen again.
Tech said the issue may e the breaker size, does that make any since? Any advice is appreciated.
This is a new unit put in within the last years time frame.
If the breaker is not kicking off, there is no problem with the breaker. You could have a compressor failing.
GFM
if i ohm out the compressor and have open circuit between start and run, open between run and com, this would rule out open overload correct? the overload is on the common line
Yes, you have a dead compressor.
GFM
it could be LRA That happen to me too what happen is the high pressure lock the rotor. check the cap if its not good then change it if its good then u have to jump start it
It was running yesterday after changed out the dual cap.( reading below spec.) Got call back this morning unit not running at all. Can it be a HPS OPEN. Thanks for your advice. I am a newbie tech.
The HPS (if it has one) is a low voltage control. The contactor should be deenergized if it is open.
GFM
So the compressor is mechanical broken . So that mean you have the replace the compressor?
I had a similar problem yesterday but my compressor was drawing over the LRA and it was short cycling on and off on and off to the point where it's about to cause premature failure to the contactor so what's the deal there GFM?
Do you mean the contactor is short cycling or the compressor overload?
GFM
This is a great video. I'm pretty sure my compressor has a locked rotor - it has been making extra womping noise during startup for several months and now it just hums and overloads. Interestingly, I have a XE 1000 like the one in this video... should I replace it with the exact OEM compressor, or do people install new and improved compressors/controls in this case? Thanks!
Go with the original on this one.
GFM
Arc flash from hard start kit @5:32. Why the tape covering holes in control section? Why the A419? For low temp strip heat lock-out?
The spark is from the contactor contacts opening. The start kit has no contacts inside. The tape is factory from Trane. The A419 locks out the A/C when ambient is below 60F.
GFM
@@grayfurnaceman OK.. Thanks.
That coil looks clogged too !
Actually it is quite clean.
GFM
Liquid slugging washes lubricant off of cylinders causing mechanical seizure.
Since you measured around 90 amps LRA and you stated that if you held in the contactor in, the thermal overload of the compressor will trip. I understand that, but why does't the circuit breaker trip?
The circuit breaker is a slow opening circuit protection because it is normal for the compressor to draw 3 times RLA on startup. The internal overload is mounted in the windings of the motor, so it senses the overload (on the compressor only) very quickly. Remember the breaker is sized for the total ampacity of the appliance +25%. The overload is sized only for the compressor.
GFM
the problem is large line is cold and the small line is cool it should be hot (any ideas )
Check out the "test meters" playlist on my channel. It may have something to help.
GFM
Does a faulty capacitor also draw amperes near the LRA value?
If the capacitor is open, yes. If the capacitor is shorted, the amp draw will be higher.
GFM
Boosters or hard starts that are aftermarket i despise. Some units come with one already on it, but in my experience if you need to leave an aftermarket booster in the unit the compressor is done. If after the one or two boosts you turn power on and off and each attempt with the boost not attached the compressor starts then that’s fine, it’s possibly just been many months the unit hasn’t been operational.
my experience with aftermarket boosts being left attached, if it’s the only thing between a compressor operating and not operating, you’ve already crossed that point where the compressor should have been replaced. anything at that point is going to be a downhill decline of the performance efficiency of the AC unit. maybe you extend the life of the unit by 1 or 2 years, but from my experience, the system efficiency is gonna have dropped before reaching that point, and having that boost on might cause it to operate but you’ll be noticing the unit is running a few to several hours more each day of use for that 1 to 2 years.
I would certainly agree that the use of an aftermarket start kit has limited value. It is extending the life of a unit close to replacement.
As for the loss of efficiency, I see very little change from the equipment efficiency when new.
Usually, the failure to start is from bearing wear that has some, but very little relation to system efficiency.
GFM
@@grayfurnaceman the efficiency i speak of would be related to secondary issues that may have caused bearings wearing out faster, i.e. refrigerant charge, dirty/contaminated refrigerant, high head pressure, etc.
what i mean by lack of efficiency is more of the unit as a whole. if the compressor bearings wore out because it was pretty old then yeah not generally gonna see efficiency issues, but if the unit is maybe less than 12 years old in an environment where it’s only used for maybe 3 months of the year and if capacitor and electrical are ok, then chances are secondary issues caused the compressor to prematurely wear. For instance a unit that was grossly overcharged one year by some other company and for the next 4 years the tenant mentioned the unit was running non stop but never bothered telling the landlord. Head pressure was very high, compressor running non stop and high compression ratio was putting more stress on the compressor as well.
the unit would give just enough cooling to be ok but it would run almost all day vs. before where it would only run for 3 to 5 hours. I do agree with your statement about efficiency, but I think it would be more of a case by case basis. more often than not i get caught up with failed compressors that aren’t that old, i haven’t come across many service calls for older ones so that’s also affecting my answer.
Not the case here but Hard start kits are great until the standard cap dies. When that run cap dies, the Hard start cap takes over but ultimately kills the compressor motor because it's not designed to do the job. That's why I dont use them.
You are correct. Hard starts are not supplied from the manufacturer, except in certain circumstances, so they are not needed.
GFM
thanks love your vidios
+Andrew Riner Welcome
GFM
Good vid bud
Doesn't locked rotor amperage occur every time you start the compressor?
It does but it is for a very short time and usually cannot be measured even with most peak hold meters.
GFM
love your videos sir!....why did it not trip the breaker tho with that very high amperage?...does it mean it tripped the thermal overload before the breaker ?... thanks !
Breakers are delayed action devices. Especially the HACR ones for A/C units. Usually, the internal overload will cut off first.
GFM
thanks again for the knowledge :)
Hi GFM, good video. Being a newbie I was wondering what is the Johnson Control A419 control for? Thanks.
1290457 In this application, its used as an outdoor thermostat to shut off the heat pump at lower outdoor temperatures.
GFM
Ok, I was kind of leading that way. Thanks for the reply.
Can compressor have locked rotor and be burn out? I was troubleshooting a unit 2 weeks ago ,and I checked the unit was pulling LR amps. First, I checked the windings with my fieldpice ohmmeter numbers did not quite match. Second, I used my Supco insulation tester which showed bad. Fieldpiece ohmmeter did not shown any continuity to ground. I ended up replacing the ac , and flush the system with R11 and put suction line filter. But I actually was not sure whether it was a burn out or not. I tried to smell but it was not really strong.
I can. The internal overload allows the compressor to start every time it cools down. This puts a load on the winding insulation. Eventually, it has to break down the insulation. I would have done what you did.
GFM
Most of the time, when windings are not giving good ohm numbers, the compressor needs to be replaced. Yesterday i had a case like that where the compressor was giving bad winding lectures and the capacitor was bad too. I replaced the capacitor, switched on the A/A. One of the terminals overheated, maybe because locked compressor, gone loose and made contact with the piping, making short circuit with the grounded piping and leaking all the gas. The compressor didnt show continuity to ground or short circuit between terminals, just did not show known ohm values.
In the end, I couldn't understand what the problem was. I have that same problem with my compressor right now, it doesn't start. It stays cool to the touch after five minutes of the fan working. capacitor's fine and contactor is fine as well.
If the capacitor is good, and power is available, the compressor is mechanically locked up. Most common failure of compressors.
GFM
grayfurnaceman Thanks for your reply. I hit it with a hammer, but it didn't start. I tested it with my meter and I get continuity in all three pins. Is there any other why I can try to unlock it and make it work? I read about some people using a rubber hammer, but I'm not sure if you need to hit it when the unit's working or when everything's off. Thanks!
For 35 years I have tried using a hammer on a stuck compressor. Rubber, 16 oz, 8 pound. Never worked. The only possibility is to install a hard start kit.
GFM
grayfurnaceman I just installed a new compressor and this is occurring. How could this be?
kiyonexus im facing same issue. Wondering if replacing booster pack will do the trick. Is there a way to test a booster pack?
It's run yesterday when I change out the dual cap (below spec.) Unstill this morning it stop.it that possible my HPS open,how do I check HPS. Its a 4 ton york heatpump. Thank you for your help Sir.I am a newbie tech.have a long way to learn.
The best
hello grayfurnaceman... some compressores don't wrote the LRA??? like Hitachi model 1000EL what can I do????
If it is drawing 5 times the rated load, it is locked rotor.
GFM
grayfurnaceman thank you.. how can I know ohming 3ph compressor and ground short???
3 phase will have the same ohm reading on all 3 windings. Check from winding to shell of compressor. Should be no continuity.
GFM
I had a tech put in a good capacitor, use one of those hard starts and diagnosed a locked rotor, but I wanted to go through my warranty company. Had their tech come out and they change the capacitor and it started working? How can that be? I believe the first tech, but how can it be locked and then not locked anymore? Told the first tech what happened and he said sometimes they free up, but if it ever stops in the same spot again, it will probably lock up again. Anyone experience this?
It has been my experience that if a compressor stops running, it will stop again, regardless of capacitor replacement. You may get some extended time out of it, but the compressor is failing.
GFM
Just horrible. I'm planning to upgrade the Outside unit completely to the new system r410 that's backwards compatable with r22, minus well. When compressor exploded it melted the coils too. So I have replace everything.
What would cause this? Can trust these AC companies around my area because their all a bunch of scams. The company changed my evaporator coil and added freon. Then all of a sudden my compressor delayed. Changed my motor fan outside but still conutined to delay(my compressor) did they add too much freon? I thinking they purposely tampered with my outside AC unit. So frustrating
Tanks
the name plate is like the old tranes from the 80s so id say at least a 1993 model because in 1994 they started using the other name plate you know not the old metal name plates but the paper name plates i call it
Yes but it wasn't cut off on low pressure gauge pressure 70/240 odb=80f r410asystem pulling 168lra rate at 158
Are you sure it is not going off on low pressure? That low side is pretty low. If the pressure switch opens, the contactor will open and close rapidly if there is no short cycle control and the compressor will probably not start due to unequal pressures. The amp draw is close enough to LRA to be a locked rotor and not shorted windings. Hope this helps.
GFM
what amps do you get when the capacitor is defective?
Amperage will be locked rotor.because if the capacitor has failed, the compressor will not start.
GFM
thanks GFM
what if the reading on LRA is higher than 92 let say 120 what does it mean.
blue moon Probably, there is a defect in the compressor windings.
GFM
Oh crap thought this was porn, this is a video, porn is mostly a video, that means i can relate to this.
lmfao me too!!
What if I replace compressor with 84 LRA to lower 45 LRA compressor?
Why? The replacement compressor is 1/2 the size.
GFM
A guy at work wiring a brand new compressor change up wrong I went back there today and rewired everything and it is locked rotor on a brand new compressor
Are you sure the wiring follows the diagram?
GFM
Yes
When I got there it was wired incorrectly they had common from the compressor and start from the compressor on the same side
I wired common from the compressor on L2 and had run from the compressor and start on the capacitor all on L 1 side
@@grayfurnaceman I don't know if he messed something up I trying to get it to run that way.
But now it's screwed
@@danpmatz You may have a burned start winding. If you depress the schrader on the suction line (quickly), and smell burned wiring, the compressor is done. You can also check the resistance of the start winding (from run to start). If open or shorted, it is done.
GFM
@@grayfurnaceman i ohlmed out compressor it read good.
I could smell a little when i took gages off
Ok.what is the reasons for compressor to drow hi amps? And what is your recommendation to fix this kind of problems ? Thank you
I can only give short answers in comments. Overcharge, plugged condenser coil, Low voltage, air in system, compressor failure.
GFM
The PTC thermistor start assist is weaker than a potential relay and start capacitor in regards to the compressor. How do you know the start kit was bad?
If you send power to Common and start rather than common and run, it will reverse the compressor which can free it up, however it will still be bad if so.
Ohming the compressors terminals they should all add up!
Example
Common to Run = 3 ohms
Common to Start = 5 ohms
then you better read 8 ohms from Run to Start which is both windings.
If it adds up they usually run unless worn tight, if electrically it ohms out put a potential relay and start cap.
Bump start by using a 300 mfd start cap touching the run cap briefly
then take the BEMF, say 300v for example
300v x .50 = 150v min
300v x .80 = 240 v max
200v x 1.20 = 360v continuous
this is how you size the potential relay.
***** Thanks for the good info.
GFM
2:20 he's immune to electric shock by the looks :)
He didn't get shocked because he didn't touch the metal contact 🤔
What's a run-wire?
There are 3 terminals to the compressor. One is common. One end of both the run and start winding is connected there. The other end of the run winding goes to R. The other winding is the start winding which has its end connected to S. Start is primarily there to start the compressor. The run winding has the majority of the electrical load as it powers the motor when running. Hope this makes sense to you.
GFM
Hard start kits are a sign of a dying compressor
Agreed
GFM
Trouble shoot tv parts.
Awfully exspensive ambient temp sensor lol, the a419
What is the gray box with digital readings?
+nellAyaR2034 Its an outdoor thermostat to shut down the heat pump below a set temperature.
GFM
+grayfurnaceman that's what I wondered. I've never seen a digital one in my area.
Wow ... I'm sure that could flummox the journeyman HVACer.
Thanks for making.
So how can one fix a lock rotor?
Sometimes the reason for the locked rotor is a capacitor failure. If the capacitor has been replaced or tested and it is still locked rotor, you can try installing a super boost starting system. The super boost is generally a temporary repair. Once you have tried these operations, the compressor must be replaced.
GFM
On a 3-Phase unit you can reverse T1 (usually red) and T2 (usually blue) changing the phasing to make the compressor run in reverse. I wouldn't do it longer than a second or so. You are just trying to backup and release the compression or stroke. As soon as it starts in reverse stop it immediately by throwing the disconnect switch. Put your T1 and T2 wires back to factory specs and see if it runs.....
I have a real SOB 2001 10 Ton Trane Voyager at the moment that this trick does not work. It's on it's second compressor in less than a month. I can't believe Trane made so many defective compressors. I got the first replacement replaced under warranty. The newest one had another accident over the weekend out of my control. The fan belt broke and was thrown. The high and low safety pressure switches did not function and kick the compressor out. That compressor must have ran all weekend and turned the evaporator and suction lines to a solid block of ice. Nice, right....that's not all. All that liquid Freon NU-22B drop-in slugged the compressor and toasted what I believe to be the internal windings thermostat.....AGAIN!
This unit has already been condemned by another company. I should have adhered to their advice as well. Oh no, no me/us....we can fix anything and everybody else wants to replace the unit for a blown capacitor or bad contactor....( ie RIP OFF)....
This unit is junk, you can't turn a turd into a diamond.
In 35 years I have tried the reversing wires trick many times and have never had it work. Of course the scrolls will not work backwards. I don't believe any manufacturer recommends NU22B as a replacement for R22.
GFM
It's a drop in replacement. Used it all summer of 2015, 2016 and Spring 2017 without issues in hundreds of units.
This unit is junk.....
Also has a restricted condensing coil I believe as well. The passages I mean, not the micro fins. I blasted 250 PSI nitrogen clear through after the pressure test. I replaced both suction and liquid line dryers. I pulled down to 400 micron.....
This unit is junk!
This unit also has no TXV.....that would have been TOO EASY!
Also has a new board and contactors........that would have been TOO EASY!
Also has 282 Volts/ 480+, plenty more than the required 277.....that would have been TOO EASY!
Also both coils are spotless and washed......Too Easy!
You can't turn a turd into a diamond.
Both GFM.
Does the unit have a low pressure switch?
GFM
Never manually push in the contractor kids. You may get hurt.