DIY Home Improvement, Remodeling & Repair Forum

DIY Home Improvement, Remodeling & Repair Forum (
-   HVAC (
-   -   heat pump Ice or frost? how much too much? (

papason 01-13-2008 12:26 PM

heat pump Ice or frost? how much too much?
This is a newer carrier unit. The fins on around the heat pump (outside unit) are white. a layer of frost or ice? covers all of them. There is some on the inside like on the lower part of the ??? small round unit with copper tubeing connected to it. It was makeing an odd noise kind of a humming/buzzing sound.
I know heat pumps frost over and then defrost. The defrosting mode may have been the sound I heard. The layer of frost was maybe 1/4 inch or less. I just dont remember how much is normal and how long it should be there. It is cold outside not sure what the temp is though.

I am a bit nervous about this system (long story) and partly because of the expese and stress of getting them repaired. Even highly recommended dealers seem to have lazy uncaring techs. I tentavly plan to install my next system and am hoping to do much or alll of the repair on this one. Cost and integrity of repair techs have me doing all of my auto and house repairs.

Thanks for helping

glennjanie 01-13-2008 03:09 PM

I hear you Papason:
I share your feelings too. It always costs too much and seldom is done correctly; I have had to do too much of their work after they have been paid.
Air to air heat pumps work best around 35* to 40* outdoor temperature. Their effieciency curve takes a nose dive when the air temp goes below 35*, and when it hits 17* there ain't nothin happening. That's when the resistance electric heat kicks on to keep you warm. The humming/buzzing sound may be an electric heating element for defrosting. Many units use a burst of hot gasses to defrost; either one costs you unnecessary money. I have seen outdoor units that looked like a big hunk of ice from the street and were still trying to work. About every hour they sound like a truck tire has been punctured (the rush of hot gas), then they start to trying to pump again.
A supplemental heater in the house will do a bang up job for you. A wood stove would cut your heat bill considerably if you could get free wood to burn in it. Or a wood fired boiler out back would be good.

jpo1 01-18-2008 08:06 PM

sounds like it just may be low on refrigerant.

All times are GMT -6. The time now is 08:50 AM.