Outside heat pump unit frozen

Old 02-07-04, 03:27 PM
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Outside heat pump unit frozen

My outside unit has been covered with ice for several days. The temperature has been consistantly below freezing, but really seems to have no impact on the problem. Today was over 40 and no improvement was noticed.
The unit works, maintaining the thermostat temp, but occasionally goes into aux heat mode. The fan never seems to stop.
I have tried to thaw it, by use of a space heater and a scrapper. But, the ice just returns.
When I first remove the ice the cycles seem normal, but as icing gets worse, the cycles are longer.
I have had problems with the unit in the past withthe motor running, and had to replace the motor as well as the controll switch.
I know there is a defrost switch, but really have no real knowledge.
Please advise.

PS: it is a carrier unit if that matters
Old 02-07-04, 03:49 PM
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defrost control is located in the outdoor unit. probably a circuit board in the electrical compartment. lowering time setting may help. may be low on refrigerant, is there a gutter above it? has it rained? it may just be having trouble catching up due to humudity
Old 02-07-04, 04:01 PM
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Yes, it has rained, snowed, and been very cold. No spout above, but could have collected some from weather. Will check for adjustment of time tomorrow after work.
Thanks for your help. Will check in tomorrow after I make adjustment.
Old 02-07-04, 04:37 PM
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Lightbulb HEAT PUMP

With all the rain and snow to get on the pump and freeze up. I would put the tstat over to AUX mod that way the fan should come on and off as heat is needed and the out door unit wont try to start when its all frozen .Then wait till the weather lets up someYou can go over to AC that is the same as the defrost mode with out the strip heaters comeing on also. ED
Old 02-08-04, 05:54 AM
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What you don't want to do is run this thing frozen over like that for an extended amount of time.

1. It could be low on refrigerant.
2. It could be a dirty outdoor coil.
3. It could be the defrost control.

We can probably talk you through checking the defrost control if you have a multi-meter and we can help you with the dirty coil. If you don't feel you can tackle any of these you need to call in the troops.
Old 02-20-04, 03:04 PM
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defrost control

change it. Even with all this the unit should have melted this long ago.
very common problem.

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