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Photograph of This new compressor was placed directly against a brick wall. One third of its condenser coil cooling ability was blocked. HVAC Compressor / Condenser Fan FAQs 2

A/C or Heat Pump Fan Condenser Unit Fan diagnostic questions & answers - FAQs 2:

More questions & answers help diagnose problems with the air conditioner or heat pump condenser unit fan

This series article discusses the diagnosis and repair of problems with the outdoor compressor / condenser fan and fan motor, including fans that wont' run, fans that run at slow speed, and fans that won't stop running.

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- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?

More HVAC Compressor/Condenser Fan Diagnostic FAQs

Air conditioning compressors overgrown with shrubs (C) Daniel Friedman

These questions and answers about the outdoor unit fan operation were posted originally

at FAN, COMPRESSOR / CONDENSER UNIT - be sure to see the diagnosis and repair advice at that page.

Avoid confusion between the indoor blower fan and the outdoor condenser fan: the compressor / condenser fan is in the outdoor unit and is used to cool the outdoor condensing coil.

If you are troubleshooting the indoor air handler that delivers cooled or heated air through the duct system and supply registers,

see BLOWER FAN OPERATION & TESTING - home.

Recently-posted questions & answers about the air conditioner or heat pump compressor/condenser unit fan:

On 2018-01-17 6 by (mod) - abnormally high voltage damaging the compressor/condenser unit?

Mark

Thanks for the updates. All of this sounds strange to me but probably we're seeing a communications gap between the technicians and the rest of us. There sounds like a confusion between volts and amps, or at the least, I'm unclear how a control board OR a bad compressor would change the VOLTAGE readings.

Central air conditioner compressors run at 120VAC or more-often 220 or 240 VAC nominal voltage.
Some units will specify an acceptable range such as 208-230VAC or, depending on your country and electrical service, up to 250VAC.

I agree that 246VAC is within acceptable limits for the supply voltage to many AC condenser units.

The AC circuit should be dedicated - it should not be also supporting other electrical equipment.

If the supply voltage (from the electrical utility) is exceeding what the equipment can handle that can damage the equipment. But you'd want to do more than just fix the equipment; you'd probably want surge protection and voltage conditioning equipment to protect the repaired compressor/condenser unit from new damage.

A typical voltage stabilizer will handle voltages ranging from 170-270VAC and will keep that voltage in the range needed by your equipment.

Research:

On 2018-01-17 by Mark

They changed the board but it still doing the same thing. They are going to replace the compressor next week. The system is running on emergency heat so the whole thing doesn't burn out in the meantime.They have never seen this problem before which is a little surprising since it's a company with 5 locations, not a mom & pop business.

They are here now to fix it. What they are going to try first is replace the Board since it's easier/cheaper. They say the stored energy in the capacitor is discharging into the compressor and the fan on shut down. We'll see...

On 2018-01-16 by (mod) -

Ok, keep me posted. What thou learn will help other readers

On 2018-01-16 by Mark

I will call them tomorrow and find out what exactly. They did recommend I have the electric company come out which I did and they said it is receiving 246 volts which is within parameters. But the company I'm having fix it says on shutting down the voltage increases.
Thanks so much for responding!
Mark

On 2018-01-14 by (mod) -

Mark,

I don't know what ribbons meant, and I would be very grateful if you could get some more detailed explanation from your contractor and then pass that on to us for understanding and research.

I am also not familiar with a compressor-motor defect that would increase the voltage level at a heat pump. However, abnormally high voltage (or voltage surges) delivered from your electrical power company's electrical grid can damage an A/C compressor as well as other electrical devices and equipment.

Typically a failing heat pump motor draws abnormally high current (measured in AMPS) not voltage (measured in VOLTS). Those terms are explained

at DEFINITIONS of ELECTRICAL TERMS - https://inspectapedia.com/electric/Electrical_Definitions.php

When a compressor motor is drawing abnormally high current (amps) that's often a sign of a failing motor - bearings are seizing making it difficult for the motor to spin. Sometimes a service tech might try installing a hard start motor capacitor as a very inexpensive step to see if she can get a bit more life out of the compressor motor.

See HARD STARTING COMPRESSOR MOTORS https://inspectapedia.com/aircond/HVAC_Compressor_Hard_Start.php

and see
CAPACITORS for HARD STARTING MOTORS https://inspectapedia.com/electric/Starting_Capacitors.php

On 2018-01-14 by Mark - outside heat pump unit voltage increases from 246 volts to 298 volts when shutting down.

My outside heat pump unit voltage increases from 246 volts to 298 volts when shutting down. Makes loud noise as it finally winds down. The tech says its something in the compressor, something like "ribbons" but was another word. Will cost $1300 to replace compressor, part under warranty, just paying labor. Any other optiions?

On 2018-01-10 by (mod) - Can a fan itself on a heat pump be bad

Yes, Including

A bad fan motor

Bad start run capacitor

Damaged fan blades

Fan loose on motor shaft

Loose motor mounts

Bad fan relay

On 2018-01-10 by Anonymous

Can a fan itself on a heat pump be bad

On 2017-12-30 by (mod) -

Not protection from the elements, but perhaps repair backup heat controls is needd

On 2017-12-28 by Carol Ann Best

Hi.i am wondering if my outside unit requires protection from the elements? I had my Mr Slim on during the winter 24/7 during one evening the unit stopped producing heat....

.the temperature in my home went from 70 to 54 degrees...During the evening. Any suggestions??? Please respond.

On 2017-08-04 by (mod) -

I'm a bit worried, too, that there is a motor or bearing or pulley failing in the air handler in your attic.

The humming is often a motor having trouble starting. We can't do more arm-waving here: you need the tech to take a careful look in the air handler to track down the noise and report to you its source.

On 2017-08-04 by MP

I had new condenser installed about a month ago, due to it tripping and a/c stops working.

A couple days later after install, there was a humming sound, with a high pitch squealing noise that's not so loud. I could hear condenser from inside the house start up loud. This noise lasts for 5-10 minutes and it regulates to the normal sound. Air coming out of house's vents is not cold.

So no a/c inside the house. With the next start up of the a/c, the cool air blows again. Tech keeps saying it's not the condenser and I need to replace everything up in the attic. I have warranty with the new unit but tech is saying the unit is fine. Can you please help? Thanks.

On 2017-07-13 by (mod) -

Michael:

The first part of the question sounds as if the fan has a bad start/run capacitor.

But your second concern could be

- the fan never runs fast enough to cool the hot high pressure gas back to a liquid refrigerant

- there is a refrigerant leak and lost refrigerant

- the compressor is not starting at all

- another defect like a bad expansion valve is not permitting refrigerant to be metered into the cooling coil

On 2017-07-13 by Michael

Trying to diagnose my problem. My outdoor fan for the condenser/compressor stopped. I am able to kickstart it with a stick. Once running by this method, however, the unit does not seem to be cooling.

The first thought is I need a new capacitor, but since after doing the kickstart, I don't get cold air coming out the vents (my blower is running), is there something else I should be checking or is it probably still a capacitor issue?

On 2017-06-13 by bill

indoor fan runs on call for cooling but no power to the condensing contactor

On 2017-06-07 by Anonymous

When I have to ac on and the fan at 1 it works great but if you turn the fan any higher the ac cuts out what could this be

On 2017-05-24 by (mod) -

Translating for other readers from Hindi to English

We have a face to face with a motor and we have a face to face.

To that rough translation we have to say sorry, I don't understand the question. Please try again.

On 2017-05-24 by Anonymous

Ac motor kai face kitnay hen aur kon kon sai face hen

On 2017-05-23 by (mod) -

Anon

Turning off the air handler at the thermostat may make some sense as running the air handler when the compressor/condenser isn't working won't provide cooling.

You can move the thermostat A/C control to OFF, or you could accomplish the same thing by simply setting the thermostat temperature well above room temperature.

Alternatively you could turn the cooling OFF but if your thermostat (or air handler limit control) has a FAN ON or MAN switch position you could continue to circulate indoor air as well as filter it - that might provide a little comfort even when the cooling system is not working.

On 2017-05-23 by Anonymous

if the blower fan motor of my central air conditioner unit stop working should i turn off the unit from the thermostat and for the air handler as well

On 2017-05-11 by (mod) -

Most often the problem you described is caused by a bad start capacitor for the fan motor. The service tech typically just changes that part to see if it fixes the trouble.

On 2017-05-10 by tom

My condensor trys to start at sometimes it will start but slow to start. When it wont start I can spin it with a stick and it usualy starts. After it runs a little while it shuts. Sown down.

On 2017-05-08 by (mod) -

Sounds like a bad fan motor start/run capacitor or perhaps (less likely) a bad control board.

On 2017-05-08 by Mark L Tucker

outside compressor fan comes on runs slow then stops turning and unit starts making a humming or squelling sound

On 2017-04-17 by (mod) -

Vaughn

Best bet is to go through the no-cooling diagnostic steps at https://inspectapedia.com/aircond/Air_Conditioner_Diagnosis.php

On 2017-04-17 by Vaughn

I call for cool air the unit comes on but the condenser dosent start

On 2017-03-15 by (mod) -

Readers: if you don't see the information you need, just post a comment or question and we'll reply asap.
Daniel

Stewart,

Normally on a heat pump in winter in heating mode, indeed ice can form on the outdoor coil and will require defrosting, handled automatically - especially when outdoor temperatures are close to freezing.

You should observe the following if the system is working normally:

- inside the heat will stop, or will switch to backup heat mode; most units have a signal or indicator light indicating defrost cycle mode

- outside the fan stops and the compressor is running.

But the requirement to go through a defrost cycle depends on outdoor temperature and humidity. So your system may not need to be defrosting as often as you think. Articles I've read on this suggest that typically you won't see a defrost cycle more often than about every half hour or 35 minutes.

If the inside indicators are defrost mode then yes I think the fan should stop - there could be a control board or fan relay control problem or an outdoor temperature sensor failure.

Watch out: as a general note for other readers, don't turn off the system in the middle of a defrost cycle - let it complete the defrost cycle or you may damage the equipment when it's re-started.

Temperzone, a New Zealand company I admire, has a nice article on the defrost cycle - at http://www.temperzone.co.nz/FAQ/Understanding-Defrost-Cycle/

Re-posting

(Nov 3, 2016) joon said:
good information, thank you admin, anyway some information share for you, i think Tower fans have one major favorable position when contrasted with other home fans: they are totally compact.

Most are extremely lightweight and permit you to rapidly lift them up to move them. Long strings compliment this element with the goal that you can move the fan into position and feel good on even the hottest of days.

On 2017-04-14 by (mod) re: why the technician intalled an "emergency" capacitor

I suspect that the technician installed a "hard start" capacitor because the standard cap was having trouble starting the motor.

On 2017-04-14 by eddieo

I just would like to know the reason somebody instead of just change the bad capacitor. He installed an emergency capacitor?

On 2017-04-11 by Anonymous

condenser making hum noise, fan not working

On 2016-12-14 by Jaron

Hello. I have a Rheem RBHP-24J18S air handler that has me pulling my hair out. One night I noticed only the blower was running with no heat coming out of the vents. The next day I climbed in the attic to check things out but didn't notice anything out of the ordinary. After some research I noticed the most common problems were sequencers, control board, and thermostats.

I actually had a new thermostat and control board for a spare so I changed them along with the sequencers.

Then set the heat on auto to start the cycle and the blower came on and a few seconds later the air began blowing out the vents harder and warm. Everything seemed to be worked fine but a few minutes later the air flow slowed down and it was blowing cool air

. I went back to checking things and found the defrost control switch was failed open so I changed it along with the watt restrictor switch. Now I don't get any heat at all just seems to be the blower blowing cool air.

I checked both sides the transformer and getting 24V and 240V and getting 24V going to the control board.

I also noticed after turning on the AC that after the cooling cycle is over and the compressor shuts off the blower continues to run for a minute or so...like the heater should do after the heating cycle is complete. Any help solving this would be GREATLY appreciated!

On 2016-10-14 by Anonymous

We recently purchased a Condo in Florida with the Condenser Unit located in a small Utility Closet on the Lanai. The unit has a 24" wide x 14" high sheet metal box and 4Ft X 24" round exhaust elbow mounted on top of the unit leading to the vent on the building wall. The noise from this 6 year old unit was unbearable.

A/C Company said everyone here has the same complaint and that we have to live with it. Wrong answer.

I installed a Compressor Blanket, cut a 10" hole in the side of the Sheet Meal Box and installed a 10" Duct that vents to the outside. What a difference. Exhaust air flow is no longer restricted and we can sit outside and have a conversation.

On 2016-09-30 by (mod) - fan motor in outside unit went bad a

Anon:

If the replacement fan motor meets the operating specs of the original one it should be OK. Moving the actual fan blades inside the condenser unit might indeed change the airflow pattern enough to be worth thinking about.

For example a typical condenser fan draws outside air IN through the condensing coil around the sides of the unit and blows the heated air UP and OUT at the top of the unit. If changing the fan assembly caused some of the exiting air to blow against the upper sides of the condensing coils you'd be reducing their effectiveness.

If the condenser unit is less efficient than it was before it might have to work harder and longer. But I think your tech will look elsewhere if the house is too warm.

On 2016-09-29 by Anonymous

fan motor in outside unit went bad and installer used different fan motor than came on unit when new now the fan is lower in unit 2 or so inches and system seams to not cool house as easy any thoughts on this one end of season now

On 2016-08-16 by (mod) - compressor failed after start capacitor replaced

Well absolutely is a pretty strong word from a nervous technician.

A wiring error or missing the real problem could either be at fault.

Often when a compressor is hard to start it's because it's seizing and at end of life - could have been damaged by a variety of problems. The tech sticks on a hard-start cap because that's dirt cheap to try and might keep the old boy cooling a bit longer. But it's no surprise if the compressor itself is shot and now needs replacement. It was probably shot before the cap was installed.

A sharp tech might have confirmed that the compressor is really shot by at least measuring the current draw at the motor.

On 2016-08-1 by Anonymous

We recently had our "Start capacitor" replaced on a 9 year old Trane HVAC. 3 days later, unit stopped cooling and technican says "compressor is shorted to the ground". When asked if the start capacitor replacment could have created any issue with the compressor shortage, he said "absolutely not".

That seems inconsistent... If the starter capacitor is a "energy booster" to the compressor, how could it be completely unrelated? So my question is, could/is it possible for a new start capacitor install create an "energy event' which would cause the compressor to short out?

The tech said there was no way they could be related technically, Just need an HVAC genius to provide their insight. I would appreciate it. I'm looking at 2400 to replace compressor or 7K for new unit.

On 2016-06-26 y (mod) - lifting the condenser unit caused it to fail?

Simply elevating a compressor/condenser up a bit would not in itself cause it to fail to operate.

Look for disturbed electrical wiring, a broken wire, a switch that was left OFF, or a thermostat wire or control wire that was broken or not re-connected.

On 2016-06-26 by Thedevotifamily

We lifted our compressor fan and placed blocks underneath so we could pour a concrete slab and now it won't kick on but the indoor unit is working. What do I look for?

On 2016-06-24 by (mod) - short life of replacement capacitor

If the replacement cap didn't give more than 8 hours of running I suspect that the motor is failing; keep in mind that some motor problems such as a winding that opens when the motor is spinning, can be hard to find. Search InspectApedia.com for ELECTRIC MOTOR TEST to see some diagnostics.

On 2016-06-24 by jesterdan

Condenser fan wasn't running. Read out the motor, Appeared good, replaced the run capacitor, came back to life for 8 hours and the fan stopped again. Any ideas?

On 2016-06-20 by (mod) - blower fan runs even with thermostat set to OFF

sounds like a bad relay, control, or shorted wires.

On 2016-06-20 by Anonymous

The blower fan on my central unit runs intermittently even with thermostat off ... The unit runs fine but this motor runs intermitently even if unit is off at thermostat... Changed thermostat and capacitor .. No help...

On 2016-06-17 by (mod)

Nice going, Jay.

On 2016-06-17 by Jay - success replacing fan motor

Thanks again for the help Daniel, That is exactly what I did Today and after cleaning and lubricating the old motor it still cut out after a while just took longer. Went to the supply house and got a new motor. I test ran it out of the unit and no more cycling.

Must have had a shorted or open turn which caused the old motor to overheat or open up. End of story, I am ready for hot weather, maybe I get another 10 Years out of it!

On 2016-06-16 by (mod)

Jay often we'll test the motor out of the unit by wiring it directly; even before doing that, if the motor shaft doesn't turn easily that's an indicator of a mechanical problem; electrical motor problems can be subtle as a winding may only open when a motor spins.

Search InspectApedia for ELECTRIC MOTOR TESTING to see more suggestions if you like. DO keep me posted.

Daniel

On 2016-06-15 by Jay

Thanks for the help Danjoefriedman, Must be the motor itself, Think I'll just replace both and see if that fixes it.

Cap seems to be OK too, On high scale of the simpson (100000ohm) get full deflection then infinitive . When I reverse the leads it is the same , no short to case. Don't see much on the 10K scale.

On 2016-06-15 by (mod) - how to test the motor capacitor

https://inspectapedia.com/electric/Motor_Capacitor_Tests.php

On 2016-06-15 by Jay

connections look OK nothing loose & full voltage all the time, how can I check the start /run Capacitor?

On 2016-06-15 by (mod)

Check for a loose connection or a bad start/run capacitor.

Keep in mind it could be a bad or failing motor itself.

On 2016-06-15 by Jay

Hi I have an old Williams AC unit Has been working fine for about 15-20 Years. When I started the AC this Year, the outside unit Fan and compressor started up OK then after 20-30 seconds the fan shut off while compressor kept running. Then the fan started again for some seconds and quit it just kept cycling. It is a 220 fan motor and the voltage stayed constant on my Simpson. What can I do?

On 2016-04-01 1 by (mod)

I can only guess, anon that someone thought the motor needed protection from weather - normally the outdoor A/C compressor/condenser is left exposed to the elements. DO NOT TURN ON this motor while it's covered in plastic. Overheating or jamming up a motor or fan can cause a fire.

On 2016-04-01 by Anonymous

there is a black plastic bag on the motor of my outdoor AC unit. Why

On 2016-03-06 by (mod)

Kevin

I'm not sure what's moving up and down - that is, if the shaft wiggles from side to side when moved against the motor bearing I suggest the bearing has failed.

But end play described as a movement of the motor shaft in and out - say by pushing or pulling on the end of the shaft so that you are pushing it into our pulling it out of the motor, as opposed to side to side against its bearings - that may be OK.

On 2016-03-06 by Kevin

My condenser fan motor shaft has up and down play but the amp draw is good. Is the fan motor still bad?

On 2016-02-06 by (mod)

Yes if you have a heat pump and if outdoor temperature is above the heat pump's lowest operating range.

On 2016-02-06 by Dave

When I turn my heat on my condenser comes on, Is this normal ?

On 2016-01-24 by (mod)

I would turn on backup heat if it's not on automatically, then call or repair.

On 2016-01-23 by Marie

Hi, I have a honeywell heat pump and the outside fan doesn't come on the inside heat is running, should i turn the inside thermostat to emergency heat

On 2015-12-08 by (mod)

Keith

The problem may be a start-run capacitor on the fan motor, or a bad control or relay.

Search InspectApedia.com for STARTING CAPACITOR to read details.

On 2015-12-07 by keith H

when I turn my a/c unit on the outside fan starts spinning and about 1 min later it slows down and like 10 seconds later it cuts back on running the way it should. it did it off and on. the air inside never gets cool enough to cool the place down.

On 2015-11-17 by (mod)

Diane

Erratic bad behaviour is particularly hard to diagnose as it tends to vanish when the service tech shows up. I'd be looking for a loose wire or a bad control board or relay.

When it wont' run, that's the time for the service tech to start doing some probing with her electrical test tools.

On 2015-11-16 by Diane

Hi,
My AC/Heat unit runs erratically. It runs perfectly on heat/or cool then it quits working. When it quits working the thermostats controls-heat,cool and even fan or auto fan will not work.

This may last for hours or days ,then it will start working again. I have had a highly recommended service company come out. First they said it was wired wrong, when they left it was working, but within an hour it quit working.

When they came back they said it was the thermostat and put in a new thermostat and a third time with another thermostat. It worked for about 15 days and then started working erratically again. Now they want to replace the main board. Any suggestions? thanks

On 2017-03-15 by (mod)

Readers: if you don't see the information you need, just post a comment or question and we'll reply asap.
Daniel

Stewart,

Normally on a heat pump in winter in heating mode, indeed ice can form on the outdoor coil and will require defrosting, handled automatically - especially when outdoor temperatures are close to freezing.

You should observe the following if the system is working normally:

- inside the heat will stop, or will switch to backup heat mode; most units have a signal or indicator light indicating defrost cycle mode

- outside the fan stops and the compressor is running.

But the requirement to go through a defrost cycle depends on outdoor temperature and humidity. So your system may not need to be defrosting as often as you think. Articles I've read on this suggest that typically you won't see a defrost cycle more often than about every half hour or 35 minutes.

If the inside indicators are defrost mode then yes I think the fan should stop - there could be a control board or fan relay control problem or an outdoor temperature sensor failure.

Watch out: as a general note for other readers, don't turn off the system in the middle of a defrost cycle - let it complete the defrost cycle or you may damage the equipment when it's re-started.

Temperzone, a New Zealand company I admire, has a nice article on the defrost cycle - at http://www.temperzone.co.nz/FAQ/Understanding-Defrost-Cycle/

Re-posting

(Nov 3, 2016) joon said:
good information, thank you admin, anyway some information share for you, i think Tower fans have one major favorable position when contrasted with other home fans: they are totally compact. Most are extremely lightweight and permit you to rapidly lift them up to move them. Long strings compliment this element with the goal that you can move the fan into position and feel good on even the hottest of days.

On 2017-02-05 by Stewart

I replaced my condenser fan motor this summer. Now that winter is here I noticed my unit is not defrosting as it should and ices up. Couple things I noted. The fan is running in the right direction. The fan does shutdown when the condenser unit shuts down, The fan continues to run during the defrost cycle and I am not sure if this is correct. Should the fan be off on the defrost cycle? What would be the cause to it continuing to run?

On 2016-10-31 by (mod)

Or could be a bad control board or relay. I'd start by confirming that there is electrical power to the unit.

Watch out: you could be killed by electric shock. If you're not trained to fool around with the compressor/condenser unit and its wiring I'd recommend hiring a service tech.

On 2016-10-31 by Ken C. allbsdd@aol.com

Have a florida heat pump system...Goodman..fan and compressor doesn't turn on...

replaced capacitor...still doesn't turn on...checked all circuit breakers, etc..did find a frayed wire ( black ) that plugs into the contactor..cut the bad part out and replaced the spade connection...still doesn't work...thermo. is set for 70 degrees..temp. inside is 78 ..

.seems like there is a reset or fuse somewhere that is bad...no noise or humming etc...Not sure where to go from here...

On 2016-09-14 by (mod)

Good diagnostic - especially if nobody gets fried.

That suggests a bad fan control, relay, or control/relay wiring.

On 2016-09-14 by deena edwards

I straight wired it in it runs good

On 2016-09-14 by (mod)

Deena

One can but guess that as the control board is new and guessing that the fan relay is on the control board the trouble is elsewhere. I expect your service tech will check voltage, loose wiring, fan motor start/run cap, fan bearings.

On 2016-09-14 by deena edwards

i bought a new coleman control board for my heat pump in the fan is only running for 3 min than cut off

On 2016-08-30 by Anonymous

condenser fan is very noisy i have replaced the fan and motor and i have leveled the unit but condenser fan is still very noisy

On 2016-07-26 by (mod)

Anonymous,

Ethel's answer is immediately below your question.

With millions of readers, sometimes I must say, with apology, that not every question gets an immediate answer.

But we continue to try our best, and hope that other generous readers who have expertise in the appropriate area will also chime in from time to time with an authoritative, informed, expert reply to reader questions.

On 2016-07-26 by Anonymous

I see peoples problems, where is the answers?

On 2016-07-17 by (mod)

Ethel, probably the problem is one of those discussed in the article above - you're on the right page.

OF course start by confirming that the outside unit has electrical power and your thermostat is calling for cooling.
Your service tech will check for:

- a bad fan start/run relay

- a bad fan start/run capacitor

- a failed fan motor

On 2016-07-17 by Ethel

My fan won't work on the outside unit, what could be causing this?

On 2016-07-04 by (mod)

OF course: just turn off power to the unit while you are waiting for repair.

On 2016-07-04 1 by Nancy Pierce

This unit isnt working to cool the house, but it is putting heat into the house. You can hear the fan by the blower running constantly. Is there a switch to shut it off or can i disconnect wires. Help im getting sick and dust is also being blown in.

The blower fan inside the furnace keeps running and its putting heat into the house when its 80degress out.

On 2016-06-17 by TODD Cohen

My central heat and air stopped working I had to look at it he said it could be capacitor do I change the capacitor the same Wilson on fan but when I put it on AC it blows breaker could I have a bad capacitor or is there another problem

On 2016-06-08 by hank .wallace

Can I safely run a 55+5 uf MFD fan start capacitor in the place of a 30+5 uf MFD both at 370 VAC or will the 55 damage the compressor?

On 2016-06-06 by Anonymous

husband put screen over top of fan to prevent sticks/leaves from falling into heat pump unit. will this cause damage to unit?

On 2016-04-30 y chris - heat pump condenser fan will run for a few minutes and shuts off

heat pump condenser fan will run for a few minutes and shuts off,the fan is red hot but won't operate. in the cooling mode the heat pump blower motor operates and blows air but the condenser fun won't run.

On 2016-04-24 by Anonymous - heat pump unit outside is not working right.

My heatpump unit outside is not working right. When the temp gets above 80 the blower that moves air though the house stops working. If I turn off the beaker for about an hour and then turn it on the unit runs normal I've had tech out several times and can't fix this. This is a Trane system about 2 years o!d. What can I try?

On 2016-03-03 by (mod) - The fan motor is now probably sho

The fan motor is now probably shot - or its start.run capacitor is shot. Leave it switched off until that's reparied. Meanwhile you're on backup heat.

On 2016-03-01 by cathy

The fan outside our unit has quit running a month before I heard a little hum for a few seconds every once in awhile now that breaker is tripped we put it back on and it tripped the breaker again so now the breaker is off the heat works fine but the blade is not turning outside could you help me with that please

On 2015-11-06 by (mod)

It sounds as if a switch remains off or is not functioning.

I found this diagnostic article by searching InspectAPedia for "air conditioner won't start"

https://inspectapedia.com/aircond/Air_Conditioner_Wont_Start.php

On 2015-11-06 by Anonymous

Outside unit fan will not come on after my husband cleaned the outside unit coils. He pulled the outside switch to cut the power but he also said that the compressor and fan were off before he pulled the outside switch. Help, he's an operator not an a/c man.

On 2015-09-10 by Nikhil Prasad

My AIR COOLER (NOT A/C) runs for sometime and then its fan and water pump shuts off but the auto swing keeps running.

On 2015-08-20 by Sridhar

3 months old General AC, out door unit fan running slowly(70%) with little humming. In the first 2 months it worked perfectly.
Can any one say the reason?? Thanks

On 2015-08-16 by (mod)

Your HVAC service tech will perhaps check current draw and look for signs of a failing compressor motor.

that's provided of course the capacitors were properly selected and wired

On 2015-08-15 by Malcolm - I changed the capacitors in two units and it worked for a while

I changed the capacitors in two units and in the addict it worked for a while and then they one went out and the fan stop spinning in the unit. I got a hard start for the other and it worked for a while then the fan stopped spinning in it as well. Neither prior to the capacitors were removing hot air. What should I do next?

On 2015-06-12 by (mod) - diagnose cause of motor overheating

If a motor is overheating that ought to be discoverable by some basic electrical tests of current draw;

On 2015-06-10 by anon

Hello, here is my problem that hasn't been fixed even after a few technician visits.
The a/c unit turns on and after a few minutes the compressor turns on blowing out cold air. However the compressor shuts off after ~10 minutes, and normal/hot air blows out. It doesn't ( or rarely) starts back on after 30 minutes.

My guess are -

Faulty thermostat

Overheating motors (which ones exactly?)

High voltage (we get higher than normal voltage in our area..the stabilizer shows a voltage of 250+..however when the voltage is in the range of 200-240, it runs fine for even up to 2 hours..coincidence or

some problem with the unit?)

Any help will be appreciated, thanks.

On 2015-06-09 by (mod) - check the motor start capacitor before replacing a fan motor

Look for a bad start-run capacitor.

On 2015-06-09 by Lill

Outdoors condenser unit starts only after manually spinning the blades a few times. Once it is off for more than an hour the same process must be repeated to make it start again

Does the fan motor need replacing??


...

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