How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask Shane D Your Own Question

Shane D
Shane D, HVAC Technician
Category: HVAC
Satisfied Customers: 32
Experience:  HVAC Technician, Author, Heat Exchanger expert. All brand heaters and air conditioners.
22766799
Type Your HVAC Question Here...
Shane D is online now
A new question is answered every 9 seconds

My heat pump is running and it is extremely cold outside.

Resolved Question:

My heat pump is running and it is extremely cold outside. Yet, the air handler, inside is not running. We had lots of snow yesterday and am wondering if it is froze up? It doesn't seem to respond to the thermostat; only to the breaker.
Submitted: 3 years ago.
Category: HVAC
Expert:  Shane D replied 3 years ago.

sed350z :

Hi, my name is XXXXX XXXXX I will be helping you today.

sed350z :

Is the outdoor unit covered in ice?

Customer :

Some of it is.

sed350z :

If you turn the power to the indoor unit, the air handler off at the breaker, does the outdoor unit continue to run....? If it does not, this may be a problem with the indoor air handler control board which is what sends power to the outdoor units controls.....

Customer :

Let me switch everything back on. I have flipped the breaker to the outside unit, so that it wouldn't continually run.

Customer :

I turned the outside unit back on and it is running, but not the air handler. I turned off the breaker to the air handler and the outside unit is still running.

sed350z :

ok.... is the outdoor fan blowing air out the top of it?

Customer :

Yes

sed350z :

Ok. Since the outdoor unit is running with no power being applied to the controls from the indoor unit, you have one of two possible issues going on.....

sed350z :

1st - The contactor. This is a power switch, that allows 240 volts to the outdoor unit, when it receives a 24volt signal from the indoor unit. The 24 volts from the indoor unit basically turns on the "switch" for the outdoor unit and allows the 240 volts to the outdoor unit and it runs..... If this contactor has failed in the "on" position, the outdoor unit will never shut off, unless you throw the breaker.

sed350z :

2nd - The unit is locked in defrost mode and there is a failure within the defrost board itself. This would be indicated by the fact that the indoor blower motor is not running with the defrost cycle.

sed350z :

how old is your system....?

Customer :

about 5 years old

sed350z :

I would say it is a toss up, as to which issue you have going on here.... The defrost board could be controlling the outdoor unit, but not sending the signal inside for the blower motor to run... If this is the case, you could put the fan switch on the thermostat to "ON" and you would have air conditioning coming out of the registers.

sed350z :

When a heat pump goes into defrost, basically it runs in air conditioning mode to thaw the ice outside.

Customer :

Would shooting warm air on the outside unit, to melt any ice, help the situation?

Customer :

When I was outside, writing down the model #, I did hear what sounded like a gas or fluid running inside of the unit.

sed350z :

not necessarily, if it is the contactor, it would still continue to run. You could put the unit in cooling, and basically you would be doing a manual defrost....

sed350z :

The sound you hear is the refrigerant moving through the system.... if the compressor is running, the refrigerant is moving.....

Customer :

I heard it when the unit was turned off

sed350z :

That is the pressures equalizing inside the refrigerant lines

sed350z :

normal sound after shutdown....

Customer :

I just turned the unit to A/C. We'll see what happens....

sed350z :

also try putting the thermostat to off. Then put the fan switch to on and see what temperature the air coming out of the registers is....

sed350z :

if it is warm, it is a contactor failure.

sed350z :

if it is cold, it is a defrost board failure.

Customer :

Should I do that now? Or wait for a certain amount of time while in a/c mode?

sed350z :

I would do it now. Keep in mind, when you go from cooling to heating, there will probably be a 5 minute delay built into your tstat....

Customer :

Okay, I have made the switch. I'll let you know.

sed350z :

remember, the "cool, heat, emergency heat, off, switch should be set to off...

sed350z :

not heat

Customer :

It is. The only thing turned on is the fan

sed350z :

perfect!

Customer :

The air coming out of the registers is cool.

sed350z :

Is it much colder than the temperature of the home?

Customer :

No

sed350z :

what is the temperature in the home now?

Customer :

70

sed350z :

can you go to the indoor unit....?

Customer :

We supplement with a wood burning stove.

Customer :

Yes, I can go to the indoor unit

sed350z :

there are two copper lines connecting the indoor unit and the outdoor unit.... The larger of the two lines (which is covered in black insulation) .... if you can feel the temperature of that line... is it hot or cold?

Customer :

It is not what I would call hot nor cold. It's as if it is at room temp.

sed350z :

If the compressor is indeed running, that line would be either hot or cold... Unless there is a refrigerant loss in your system. This still would not explain why the indoor blower motor isn't running if the outdoor unit is in defrost, and not able to defrost because of the refrigerant loss. So there may be more than one issue going on...

sed350z :

OR

sed350z :

the outdoor unit is only running the fan motor and not the compressor, which isn't very likely....

sed350z :

Given the temperatures and conditions you are currently under, you are better off running the electric heat only anyway.... The heat pump if it were operating correctly would not be producing very much heat now....

Customer :

Is this what happens when the "fan only", is switched on?

sed350z :

the reason you are getting close to room temperatures out of the registers with the outdoor unit running and the fan manually set to on, is the same reason why the large copper line is room temperature....

sed350z :

because enough refrigerant is not moving through the system....

sed350z :

If you heard the pressures equalize outside as you said earlier, I believe the compressor is indeed running, the system however does not have the correct refrigerant charge....

Customer :

I will call a local company tomorrow and have them come out.

Customer :

My next question is how do I set the themostat so that it is elec. heat only?

sed350z :

set the thermostat to emergency heat, and turn the breaker to the outdoor unit to off. Call for an hvac tech to check the refrigerant charge in the system

sed350z :

the charge in the system, and the lack of the blower motor running with the outdoor leads me to believe you have two issues going on at the same time unfortunately....

Customer :

Will do. Thanks for your help.

sed350z :

Sure thing. Sorry that I couldn't narrow it down any further for you. Please let me know if there is anything else I can help you with. Thanks, Shane

Shane D, HVAC Technician
Category: HVAC
Satisfied Customers: 32
Experience: HVAC Technician, Author, Heat Exchanger expert. All brand heaters and air conditioners.
Shane D and 4 other HVAC Specialists are ready to help you

JustAnswer in the News:

 
 
 
Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.
 
 
 

What Customers are Saying:

 
 
 
  • You did one super job of explaining to me everything there is to know about this fridge. I'm looking forward to asking you questions in the future. Jimmy Bagley, IA
< Last | Next >
  • You did one super job of explaining to me everything there is to know about this fridge. I'm looking forward to asking you questions in the future. Jimmy Bagley, IA
  • Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C. Freshfield, Liverpool, UK
  • This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!! Alex Los Angeles, CA
  • Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult. GP Hesperia, CA
  • I couldn't be more satisfied! This is the site I will always come to when I need a second opinion. Justin Kernersville, NC
  • Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around. Esther Woodstock, NY
  • Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know. Robin Elkton, Maryland
 
 
 

Meet The Experts:

 
 
 
  • gotoman for ac

    HVAC Technician

    Satisfied Customers:

    4657
    51 years of experience install design and repair of all makes and models of AC
< Last | Next >
  • http://ww2.justanswer.com/uploads/SE/ServiceTechRus/2012-6-7_2119_056.64x64.JPG gotoman for ac's Avatar

    gotoman for ac

    HVAC Technician

    Satisfied Customers:

    4657
    51 years of experience install design and repair of all makes and models of AC
  • http://ww2.justanswer.com/uploads/AL/alumalite/2012-5-10_234018_shutterstock506249951forJA500.64x64.jpg Phil's Avatar

    Phil

    Mechanical Engineer

    Satisfied Customers:

    3888
    Retired HVAC/ Electrical & Boiler contractor. Industrial
  • http://ww2.justanswer.com/uploads/skibum0101/2008-12-16_015819_just_answer.jpg Rick Mather's Avatar

    Rick Mather

    HVAC Technician

    Satisfied Customers:

    3132
    35 years experience, HVAC
  • http://ww2.justanswer.com/uploads/RY/Rygis20/2011-5-7_3143_DSC5324.64x64.JPG Matthew's Avatar

    Matthew

    HVAC Technician

    Satisfied Customers:

    1994
    14 years experience in the HVAC field of service, installation, Manual J & D calculations
  • http://ww2.justanswer.com/uploads/KE/kentguidry/2011-9-26_214316_0059.64x64.jpg Kenton Guidry's Avatar

    Kenton Guidry

    HVAC Technician

    Satisfied Customers:

    962
    12 years install/service experience.
  • http://ww2.justanswer.com/uploads/solarman1947/2009-12-13_223915_phpkKBcXq_c2PM.jpg Rick Ridley's Avatar

    Rick Ridley

    UK Heating Engineer

    Satisfied Customers:

    871
    Retired But have had 30 years on the tools, Ex CORGI
  • http://ww2.justanswer.com/uploads/Ironheadfan/2009-12-18_222416_pump_005.jpg Tom's Avatar

    Tom

    HVAC Technician

    Satisfied Customers:

    770
    16+yrs HVAC/R service. Residential Commerical Industrial
 
 
 
Chat Now With A HVAC Technician
Shane D
Shane D
HVAC Technician
32 Satisfied Customers
HVAC Technician, Author, Heat Exchanger expert. All brand heaters and air conditioners.