Photograph of  This new compressor was placed directly against
a brick wall. One third of its condenser coil cooling ability was blocked. A/C Compressor Hard Start FAQs
Q&A on AC compressor that has trouble starting Set#2

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Q&A on hard-starting HVAC compressor motors:

These questions & answers about hard-starting air conditioner or heat pump compressor motors help diagnose why the motor may hesitage, be slow starting, or may continue to burn out the starting capacitor.

This air conditioning repair article series explains procedures for the diagnosis and repair of hard-starting air conditioning compressors.

Green links show where you are. © Copyright 2017, All Rights Reserved.

FAQs on A/C Compressor Hard Start or Intermittent Run or Stutter

Photograph of  This new compressor was placed directly against
a brick wall. One third of its condenser coil cooling ability was blocked.These questions and answers about HVAC compressor motors that have trouble starting were posted originally at HARD STARTING COMPRESSOR MOTORS

Photo: a motor starting capacitor, a common repair effort for hard starting AC compressor motors. [Click to enlarge any image]

On 2012-06-30 by (mod) - system runs for 10 minutes and stops


If the system runs for 10 minutes and stops, it could be overheating - maybe a failing motor; it's common to try swapping in a start/run cap first though.

On 2012-06-30 by xXxColdShotxXx

I have been having problems with my outdoor A/C unit. It will start, but after 5 to 10 minutes the motor just stops turning and it just hums and it starts blowing warm air through the ducts. What do you think may be wrong with it, is it a bad capacitor or relay or what? Thanks for any help.

On 2012-06-21 by John

Thanks very much for the advise!

On 2012-06-21 by (mod) - I have to bang the side of my York compressor to get it started


Sometimes when mechanically disturbing an appliance gets it running we trace the problem to a bad start relay or contactor, or to a loose electrical connection. I'd as the service tech to check the system's operation for those or some other difficulty.

On 2012-06-21 by (mod) -

Amanda, you need to as your HVAC service company to send out an experienced service tech. The problem may be a hard starting motor - or something else, we can't tell from your email.

On 2012-06-21 00:24:23.172073 by John

Hello, Appreciate any help; At the beginning of each summer I have to bang the side of my York compressor to get it started.

The fan blades start spinning and the compressor kicks in immediately after I bang it with my hand. I’m banging the area where the capacitor and wires (switch?) reside. The unit is nine years old. Any idea what part(s) may be bad?
Thanks very much!!

On 2012-06-20 23:46:09.925687 by amanda

any help will be really appriciated.. ive been having many issues with my air this yr which is aggravating since the unit is only 3yrs old..

first i had a issue with it not cooling and i had a tech out he said my coils needed clean so i had that done and it worked good for 2 weeks now it struggles to keep up it never gets as cool as what the thermostat is set to if i have it set on 72 it will get to 74 but not any lower, now in the late afternoon or early evening the outside unit turns off (furnace still running)

i check the breaker and its never tripped but the only way i can get it to come back on is if i turn the breaker off for a minute and turn it back on. the first time i did that it came right back on but the second and third time i had to do it a few times before it would come on.. the pressures have been checked and they seem to be what they are suppose to be.

i have a child with medical problems and she cant be in the heat, and im lost on what to do my grandfather was a repair man yrs ago but with things being more "updated"

and hes not familar with a/c with heat pumps now he doesnt know where or what to do and with my finances being tight he doesnt wanna cost me money i dont have replacing things that dont need replaced..thanks for any advice

On 2012-06-19 19:46:33.788762 by (mod) -


Except when the service tech is diagnosing and fixing a problem, there is just a little simple annual service/inspection that is needed for the outside compressor/condenser unit. Inspect the unit for physical damage such as smashed cooling fins, debris blocking the cooling fins on the condensing coil, obstructions sticking into the unit, trash and debris or shrubs around or close to the unit that might obstruct air flow or interfere with fan operation.

A more subtle inspection point involves noticing oil deposits on the refrigerant line service ports - indicating a refrigerant leak.

Other defects such as loose components show up as sounds or noises.

Still other defects that need repair include signs of loose or burned wires, lost refrigerant piping insulation, unit out of level.

On 2012-06-18 18:28:44.451746 by N BALASUBRAMANIAN


On 2012-06-18 00:12:30.023607 by (mod) -

Tim, you have already done the hard part of this diagnosis.

Dimming lights can indicate that an electric device is drawing high current - which in the case you describe may be the compressor motor trying to start. The cycling is because it tries, overheats, stops on thermal reset, cools off and tries again;

The burned wire you found at the capacitor may mean that (if you are lucky) just the capacitor has failed - replacing it may get that motor running again. But if the compressor motor itself has seized, replacing the capacitor will show that the motor still can't start.

"BURNED-OUT COMPRESSOR" discusses how we diagnose a burned out compressor.

(Found in INDEX to RELATED ARTICLES at our Continue Reading suggestions at the end of this article)

and at "CAPACITORS for HARD STARTING MOTORS" we discuss troubleshooting the start/run capacitor.

WATCH OUT: if you are not trained and lack expertise, you can be shocked or killed (or start a fire) working on electrical equipment.

On 2012-06-16 17:29:32.574415 by Tim

After I noticed my central air wasn't cooling I turned it off for awhile and tried to re-start, I noticed that every 20- 30 seconds my lights would dim a little as if a large electrical draw then release. I turned the system off and began researching this site ( an excellent service I might add).

I took the cover off the unit out side and immediately noticed the red wire connected to my capacitor was just resting on the terminal as it was completely burned and charred. Did I get lucky and find the problem or do you think this is a symptom of a different issue.

On 2012-05-30 13:26:14.235058 by (mod) -

Thanks Ronald for the very nice comments. We work hard to make our information useful, accurate, unbiased. So reader feedback, including questions, comments, and polite debate, are very helpful.

On 2012-05-30 13:25:36.402324 by (mod) -

Thanks Anthony, your views are helpful, though I'm not sure we agree; a burnt up wire could be caused by a variety of problems, even a nick and short circuit, but more likely by overheating due to overcurrent due to a problem in a relay or in the compressor motor itself. A burning up wire to a compressor is less likely to damage the compressor than vice versa.

On 2012-05-29 21:24:23.412629 by Ronald

I want to Thank You for posting this wonderful info....I was able to follow your instructions and get my AC up and running..!!!

To those who are attempting to D.Y.I...make sure your circuits are off ..!! I am a Residential Remodeler by trade and am well versed in working with electrical and I still checked and double checked that everything was off before working...Good Luck..!!!

On 2012-03-26 13:29:50.402138 by Anthony

I am an E.E. The comments above regarding the "Could be" is correct, in fact I would say it's likely a burnt wire caused the comp to fail. Greater than 90% probablilty based on the outline of events. However, a lot of what was described above regarding motor start up in the reply is misleading, and somewhat incorrect.

On 2012-03-17 22:00:16.992705 by I am having central air conditio

My central air conditioning unit has been giving me trouble for a few years now.

Sometimes, when you turn it on at the thermostat it works, and sometimes it doesn't. If it does work, it usually quits before it should. A fan or something is still going, but the cooling part that makes the louder noise outside quits running. Sometimes, you can manipulate the spring thing at the thermostat by pulling it back and letting it go and it will start. Do you know what the problem could be? Thanks.

On 2012-01-09 23:50:38.181121 by (mod) -


I'm afraid the answer is a definite ... maybe. For example if the compressor was slugged with excess liquid refrigerant it could have been internally damaged.

Also, and this is not quite an "excess" of refrigerant gas, on some, at least older refrigeration systems, if someone switched the elecrical power on and off too rapidly or too frequently, the compressor could find itself trying to re-start against a high head pressure - with difficuly.

Whereas normal on-off (less frequent) cycling on and off of the compressor gave the gas pressure time to equalize between the high and low sides of the system, reducing head pressure and giving the compressor an easier re-start.

Finally, a clog or blocked refrigerant line that slows or does not let the high pressure side bleed down and equalize when the compressor is off will also make the compressor hard-starting.

On 2012-01-09 00:01:30.941465 by samy salman

could an excess of the coolant gas cause hard start up problem ?

On 2011-12-24 02:30:01.545174 by (mod) -

Mel I think there is no need nor reason to install an extra start capacitor when the present one is working adequately.

The addition of a hard start capacitor kit makes sense if your existing capacitor has failed, OR if you are trying to squeeze a bit more use out of a failing hard-starting compressor motor.

My reasoning is that if we exclude a motor that is hard starting because the capacitor is bad (just replace the capacitor) then other reasons for hard starting motors are not innate to the capacitor but to other causes that won't be avoided by the capacitor.

Comments welcome.

On 2011-12-23 23:29:24.952119 by Mel

Should a "Hard-Start Kit" be installed on an air conditioner when no problems arise? Will installing one prevent problems and will the a/c unit last longer if installed?

On 2011-12-06 02:16:12.380277 by LEONCIOMADRONERO


On 2011-10-09 23:52:54.004725 by Peter

DanJoeFriedman, thanks for your advice...I requested a more experience tech, who was able to locate some lose wiring that has seemed to fix the problem...All best, Peter

On 2011-10-03 22:36:13.062981 by (mod) -

TX Red: slow pressure equalization when the compressor is OFF indeed suggests a blockage that needs to be found and fixed; perhaps at a drier/filter or at a thermostatic expansion valve or cap tube.

Dan F: it sounds as if your compressor is not starting. You need a service call. Possibly a hard start capacitor kit will help but I'd like to see some diagnosis first.

Chandra: back in Sept you described what sounds to me like an overcurrent due to a seized motor. What did your service tech find and do?

On 2011-09-19 10:48:16.263502 by Waqar Zaidi

Hi DanJoeFriedman, my 4 months old AC is having starting problem as i told you previously, i observed that when the compressor starts for the first time its take 2 to 3 tries to get start then works fine even after its thermostat gets satisfy it starts again fine. what could be the reason of 2 to 3 tries to get start 1st time?

my breaker never triped and its compressor never stop working while running it stops only when i stop it or its desired temperature reached. cooling is also fine no icing etc. i am concerned about its compressor only is it fine coz its new and in warranty.

On 2011-09-14 02:56:04.949554 by dan f

When set to cool, my a/c makes a humming noise for about 30 seconds before quitting and not blowing anything. What can I do?

On 2011-09-09 18:17:24.759916 by Texas Red

...not exactly sure what a compressor start relay is. Is it wired into the compressor itself, or is it located in the control box among capacitors, terminals, etc?

If its contacts were burned or otherwise damaged, wouldn't the solution be to replace the relay rather than install a hard start kit? I watched the intallation of the hard start kit and am pretty sure he just confirmed that the compressor was drawing too much amperage at start up and therefore required the kit.

He attributed the high start up draw to slow pressure equalization somewhere between evaporator, condensor, compressor(??) Not sure specifically where or how the uneven pressure was creating a problem.

On 2011-09-09 05:58:42.387194 by chandra

Please also provide cost if there is any problem or repair requires, thanks again!

On 2011-09-09 05:08:10.103113 by chandra

My attic fan or blower makes huge sound and circuit breaker trips off when I start my AC. I bought the new home 3 years back and we use AC very less as we prefer outside air. Please share your experiences or let me know if you know the problem or resolved the similar problem. Thank you!

On 2011-09-08 16:56:28.795593 by (mod) -

Your thesis is reasonable but not, IMHO, absolutely proven by events.

A compressor start relay (or most other switches) that are loosely wired will typically experience arcing at the loose connection (an event that can, by the way, when the circuit is active or the switch closed, draw higher amps than normal due to the resistance at the point of arcing and corrosion.)

I've posted our conversation in this article in the Q&A just above the Comments Box section.

On 2011-09-08 15:54:46.108413 by Texas Red

Thanks, Dan. I didn't communicate the timeline very well in my original post.

In 2009 tech # one had come to respond to my problem of a 4-year-old compressor kicking the circuit breaker. Without even looking at the connections in the shut-off box adjacent to the unit, he went straight into control panel, checked compressor current draw at start-up and installed a hard-start kit. I thought it odd that a compressor less than five years old would be drawing too much current.

Had no problems in 2010 but last month the circuit breaker started kicking off again late in the day. Tech #one returned, checked coolant pressures and return temp, added some freon and started to pack up.

I asked if he wasn't going to check the current draws. He reluctantly removed the control cover, checked draw and voltages and pronounced the unit was running perfectly before leaving with my $168 check. When the circuit breaker kicked off again the next day, I started to suspect the breaker might be worn out.

Called an electrician a few days later. He replaced the breaker switch, again without checking the connections at the shut-off box, and within eight hours my compressor had died - coils shorted to ground - confirmed by tech # one who quoted me a price to replace the unit.

Now I called a contractor I knew asking if he knew any good AC techs. He referred me to tech # 2 who, in my first call, was immediately suspicious that my original problem may have been in the wiring, not the unit. His reasoning was that a compressor less than 5 years old shouldn't have been giving me problems to begin with.

He came over to confimr my compressor was shorted out.

He then did what no other tech had done since I owned the house - popped the cover off the shut-off box and tightened the leads at the terminals - black wire loose, white wire "very loose." My question is whether that may have been my problem all along and would a hard-start kit have temporarily releved the symptom -tripped circuit breaker- without curing the problem.

On 2011-09-05 20:06:11.491803 by (mod) -

Josh a bad capacitor can cause revresopreation, Ty replacing the start-run cap

On 2011-09-05 19:14:53.878216 by Josh

My (indoor) fan motor studders and goes back and forth in forward and reverse. It finally starts turning in the right direction but it doesent have full power, and then it eventually dies down to a slow creep and begins to make a light humming noise..

I think it may be the Dual Capacitor... Could anyone help me with this problem, any advice will be greatly appreciated...

On 2011-09-01 03:52:32.636190 by (mod) -

An HVAC compressor that does not produce any pressure sounds as if it's broken internally. I'd ask for a check by an HVACR technician

Byran: it sounds as if you have a hard-starting compressor - it may be at end of life but often it's worth asking an HVAC tech to try an hard-start capacitor kit.

On 2011-08-28 22:41:43.602041 by Julius

My compressor runs but does not pump ( pressures remain equalized) it eventually shuts off and then runs again but with the same results. Doe you know what is causing this?

On 2011-08-27 11:39:22.779830 by Bryan

Compressor will not start. Fan runs, air handler fine. When I pulled the outside (fuse? the electrical plug on outside wall that disconnects the electrical input) and then push it back it, the compressor begins to start, for a second, then stops. The top of the compressor/condenser unit stays warm, steam comes off of it when water squirted on it.

On 2011-08-26 18:13:24.767398 by (mod) -

Scott, did you look at the HVAC noise diagnostics beginning at NOISY AIR CONDITIONER / HEAT PUMP (Found in INDEX to RELATED ARTICLES at our Continue Reading suggestions at the end of this article)
There we discuss humming and buzzing noises and possible sources. You need to start by being sure you have traced the sound to a specific piece of equipment; then look at motors, capacitors, relays as we describe in the article.

On 2011-08-26 02:00:27.434117 by Scott

2nd Request...My Central Air unit (Carrier) makes a buzzing/humming noise briefly when it starts. Kind of like a transformer winding noise. It is not heard at the compressor unit. The fan circuit has also been ruled out by disconnecting the compressor circuit and starting the furnace fan, etc. Any suggestions??

On 2011-08-26 00:20:18.260297 by (mod) -

Clare I doubt anyone can even guess at a diagnosis of what's wrong with your system with so little information, but it's reasonable to ask the service company to return and figure out what happened. Let us know what you're told.

On 2011-08-26 00:19:20.756472 by (mod) -

Peter, talk with the HVACR service manager before having anyone sent out again. Politely ask him to send someone with much experience and training so that you don't keep repeating service calls. It may seem profitable to the service company to keep returning, but I doubt they want a bad reputation.

On 2011-08-25 23:13:47.283028 by Clare

Would anyone know what these guys could have done to my unit. Have never had problems just had it serviced once a year.

On 2011-08-25 23:12:38.856599 by Clare

I had our air units serviced yesterday and now one unit's fan will not run ?

On 2011-08-20 21:41:22.759388 by Peter

a few months ago my condenser began shutting down before it would reach its set temperature... had service in who replaced a circuit board after much deliberating and I think a capacitor...It worked perfectly for a few day through a stretch of 100+ days...then it returned to its previous behavior..

.I didn't use the system and checked for a once or twice a week to see if the rest had done some good...

About 4 weeks from the last time it worked properly, I tried it again during another 100+ degrees spell and it worked like a champ again...consistently lowering the internal temperature nearly 30 degrees from the outside..

.This lasted for about 4-5 weeks and three days ago returned again to it previous bad performance..

.I have had service twice and am gettng ready to make another call...

Any thoughts? Many thanks, Peter

On 2011-08-16 00:48:38.041665 by tammy

fabulous info. thanks

On 2011-08-15 18:40:31.033308 by (mod) -

Stanley typically when the compressor/condenser shuts off and won't operate for several hours it's a sign that a motor is overheating and being turned off by a safety switch. Often thermal overload switches on electrical equipment will automagically reset themselves once the equipment has cooled down.

If it's your outside compressor/condenser unit that's switching off you can confirm that it's overheating by gently cooling the system down with a garden hose (it is designed to tolerate rainfall, for example).

If your unit has blocked airflow due to shrubs or something else or if its condensing coil or fan are blocked by debris (like grass clippings) it may be possible for a homeowner to fix that condition by cleaning or hosing off the equipment or cutting back shrubs too close to the unit.

In any other case you need an HVAC tech to diagnose and fix the cause of overheating.

On 2011-08-15 18:36:45.611562 by Stanley Franklin

Air conditioner starts however after about 5 hours the outside unit shuts off and then won't come back on for several hours.

On 2011-08-08 20:42:25.287271 by (mod) -

Sam provided the new capacitor is properly selected and wired up, it's time to have some tests of the motor itself, its start and run windings, to see if it's usable.

Other diagnostics can rule out a problem, for example with the thermostatic expansion valve or a refrigerant system clog that was causing overpressure and the motor to go off on reset.

On 2011-08-08 18:24:21.941895 by Sam

On 8-6-11 a a/c repairman put a hard start kit on my unit, later the unit stop cooling. He
came back and restarted the compresser, again a few hours later it stop cooling. What to do at this point, please advise me.

On 2011-08-07 03:12:37.418088 by tungnguyen

how much for replacement the motor of air conditioner ,

On 2011-08-06 23:52:42.739797 by (mod) -

tripping circuit breaker means overcurrent means a motor that either cannot start or is seized.

On 2011-08-06 22:45:31.766486 by Mark

My condensor trips my circuit breaker, the compressor fans starts but not the compressor(Nor does it hum). When I try to short the capicitor there is no spark. Is it possible that the capacitor is to blame or more unfortunate, the compressor?

On 2011-08-05 22:13:21.814196 by (mod) -

I think the thing to do is take out the motor and test it stand-alone.
I'd think your tech would also check
- proper wiring connections
- proper voltage (not low voltage)
- that the motor ratings and wiring connections match the actual voltage (some motors can be wired for 120 V OR 240V)
- that there is no binding in motor mount or drive - if the motor were not properly mounted, or if the fan it's trying to spin has seized bearings or a crooked, bent shaft, the motor may be unable to turn the blower shaft - that's a reason for testing the motor out of the unit.

If all of those look good it must be a local wiring or control board problem. But the humming sure sounds like a bad motor, capacitor, or low voltage.

On 2011-08-05 22:00:00.052698 by Amy Sparks

even if we just put a brand new motor and capacitor in it? could it be anything else?

On 2011-08-05 21:57:28.124744 by (mod) -

Amy you may have a bad fan motor, bad start relay, or control board.

On 2011-08-05 21:53:14.855952 by Amy Sparks

the unit comes on hummms light air not turning. replaced fan motor and capacitor. does the exact same thing! light air flow hummm but fan not turning! help!

On 2011-07-29 16:26:09.411412 by (mod) - thanks for the Kudos to InspectApedia - we take care to remain independent & unbiased

Thanks for the nice note Ms. Ruiz. We publish information in some depth on most building topics. Among problem diagnosis and repair steps, there are many that are well within the scope of most homeowners or occupants, but of course other steps require expertise and special equipment.

Even in the latter case the more you know about the general approach to solving or preventing building troubles the better you can understand what's being proposed or done by your contractor.
InspectAPedia is an independent publisher of building, environmental, and forensic inspection, diagnosis, and repair information for the public - we have no business nor financial connection with any manufacturer or service provider discussed at our website.

We are dedicated to making our information as accurate, complete, useful, and unbiased as possible: we very much welcome critique, questions, or content suggestions for our web articles. Working together and exchanging information makes us better informed than any individual can be working alone.

On 2011-07-29 16:09:05.153600 by Bertha V Ruiz (female)

Thank you so much for this info. I am trying to familiarize myself in how hvac works. It hcosts so much for any service call. Not to mention the labor and parts. I am glad that this info. is free for one to just read and take notes. to know-how and what to look for.

On 2011-07-28 23:53:28.271729 by (mod) -

Chris short cycling A/C compressors combined with that loud startup noise sounds like the system is shutting off on thermal reset. I can't say if it's a bad relay, control, or motor, but you need a service call.

On 2011-07-27 02:39:49.978389 by Chris

My A/C unit just started turning on and off very frequently. The unit starts, making a loud noise at first, runs for about 20 seconds or so, then shuts down. This is a continuous cycle. The system is about 10 years old, and I have not been running it very hard, with the temp set at 85 degrees. Any clues as to what the problem is?

On 2011-07-24 15:37:15.526948 by (mod) -

Anna what's recommended - a hard start kit - for your compressor motor - sounds like a reasonable thing to try in that it's much less costly than replacing the A/C system. If your mobile home park has inadequate power service to the whole community you might see that as low voltage (that can be measured or even monitored) or perhaps dimming lights.

On 2011-07-22 00:09:17.700882 by Anna

Sometimes my ac will come on and sometimes, it will not. I was told the problem is because I live in a older mobile home park that can not handle the amount of power needed for the 105 residences to run ac units on a hot day. I was told I should have a hard start installed on my ac. It is a Rheem 2.5 that is approx. 10 yrs old. Does this seem logical?

On 2011-07-19 16:41:31.180319 by (mod) -


To get a functional transfer of heat from the condensing coil to outside air we need at least 15 degf. temperature difference.

When the weather is extremely hot outside it might be that for some systems the ambient air temperature is getting close enough to the temperature of the high pressure high temperature gas exiting the compressor (and entering the condenser coil) that the system has diminished cooling capacity. Temporarily cooling down the whole outside system increases the system efficiency but only briefly.

Make sure your compressor has good air flow, not blocked by a building, plants, etc; some folks try adding shade over the unit; If it continues to overheat I'd ask for an opinion from an experienced local service tech.

On 2011-07-19 16:38:38.767924 by (mod) -

Bob: the way most capacitor kits work they are intended to be added on to the existing wiring in parallel. A second capacitor wouldn't damage the compressor so much as keep a failing compressor limping along a bit longer before it seized up for good.

On 2011-07-18 23:09:20.015261 by Christopher

My air conditioner compressor runs fine till it gets really hot outside, about 3:30 I have to get out the hose and spray off the lines and then it will start and run all night. Any Ideas what is wrong the unit is only 6 years old and has always done this.

On 2011-07-18 17:52:36.760305 by Bob:

there are two hard start kits on my air conditioner. I know that there should only be one but some tech installed a second one a few years back and didnt remove the first one. My question is would having two hard start kits cause a compressor to go bad.

On 2011-07-06 16:15:21.368687 by (mod) -

Brent: RE: One of the connections on my compressor has literally burned up. I replaced the cable/connection and cleaned the lead on the compressor but the compressor still doesnt come on"

a burned up electrical wire connection at an air conditioning compressor can happen for several reasons but one of them is that the motor is frozen and can't start; when the stuck motor tries to start it draws high amps and can over time burn the electrical connection before the breaker trips. Sounds like you need a service call from a trained tech.

On 2011-07-06 16:13:43.761393 by (mod) -

Andre: re: "my compressor won't turn on" - if you hear the motor trying to start but it's not starting you might be able to get the compressor going by having a hard starting capacitor kit installed.

In the article series
see the article titled CAPACITORS for HARD STARTING MOTORS

(Found in INDEX to RELATED ARTICLES at our Continue Reading suggestions at the end of this article)

On 2011-07-06 16:11:42.074937 by (mod) -

Eric: re: "100 degree days have my compressor shutting down during the hottest part of the day" - your compressor may indeed be at end of its life, but there are some things to check: can you make sure it's got good air flow through the unit, that the compressor is not too close to the building, blocked by shrubs or trash?

You could also try temporarily shading the unit with a beach umbrella to see if that makes a difference and extends its life.

On 2011-07-06 13:57:01.017077 by Eric Y

I live in Texas and lately the endless 100 degree days have my compressor shutting down during the hottest part of the day. If I spray cold water it comes back on and runs the rest of the day. The AC Tech says I need a whole new unit. What's your take on this.

On 2011-06-23 01:38:28.770415 by andre

my fan run but my compressor won't turn on ....i hear it tryin to jump on but it wont..what do i do for this problem

On 2011-06-19 06:42:45.138150 by Brent

One of the connections on my compressor has literally burned up. I replaced the cable/connection and cleaned the lead on the compressor but the compressor still doesnt come on. Any ideas?

On 2011-06-16 21:19:54.363107 by (mod) -

Brenda: re: "i have changed the breaker the capacitor switch and it sparks when i turned the breaker on "

This sounds DANGEROUS - leave the equipment off until it's checked by a trained HVAC tech or a licensed electrician. I can't say if the failure is in the equipment, wiring, or breaker/panel but it sure sounds like a short circuit that could start a fire.

On 2011-06-16 21:18:21.137203 by (mod) -

Yep, it could be a bad start / run capacitor - and that's less costly than replacing a bad fan motor so I'd try that. Can you spin the fan blades easily (with power off) ? If so the motor is not seized up fully (yet)

On 2011-06-09 15:58:19.881689 by Craig Barnes

I have a blower fan that will not continue to run...It will start to rev up than it's like the voltage drops and it slows that stops ?... can this be a start Capacitor problem?

On 2011-06-09 14:52:41.853163 by brenda

i have changed the breaker the capacitor switch and it sparks when i turned the breaker on

On 2011-06-02 16:18:52.978132 by (mod) -

Grant: that question is beyond my expertise - I'll do some research on starting capacitor options and will report back here.

On 2011-06-02 16:08:43.064764 by (mod) -

Lonny, did you check the circuit breaker at the main panel?

Provided that you are trained and know how to safely make basic electrical checks, if you have power at the main panel, then shut off power there (on the circuit to your compressor unit) and check the continuity of the wiring and wiring connections.

Watch out for fatal electrocution hazards!!

On 2011-06-02 01:18:34.791602 by lonny

Had a compressor not getting power,change the circuit breaker still not getting power to the unit

On 2011-06-01 20:58:05.055985 by grant

i have been asvised that on a hvac run capacitor, 370volt can be replaced with a 440 volt(45+5 uf) and that compressor will only draw power that is needed and extra available voltage wont cause a this correct?

On 2011-05-21 11:53:12.733798 by (mod) -

Yes, a starter capacitor can fail without bulging. If in doubt it's often an inexpensive diagnostic test to simply swap in a new one.

On 2011-05-20 22:21:41.643505 by Frank

If a start capacitor goes bad, can it just get weak or will it most likely bulge out?


Continue reading at HARD STARTING COMPRESSOR MOTORS or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.


Suggested citation for this web page

HARD STARTING COMPRESSOR MOTOR FAQs-2 at - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.


Or use the SEARCH BOX found below to Ask a Question or Search InspectApedia


Frequently Asked Questions (FAQs)

Click to Show or Hide FAQs

Ask a Question or Search InspectApedia

Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.

Search the InspectApedia website

Comment Box is loading comments...

Technical Reviewers & References

Click to Show or Hide Citations & References

Publisher's Google+ Page by Daniel Friedman