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hely2010

Fol-up on 'Heat pump blows cold air on defrost'

hely2010
13 years ago

I didn't really see a resolve on the http://ths.gardenweb.com/forums/load/hvac/msg1122511412939.html?23 thread. AND, my problem may be slightly different, although we also get no heat when in defrost mode-but we have NEVER gotten heat. I am hoping someone can help us, or let us know if it's a "this is the way it is, live with it" type situation.

Installed April, 2010: Amana ASZ160361 - 16 seer, 3 ton heat pump

AEPF313716 Air handler w/8kw heat strip

Numerous problems with installation that we were told are now corrected (it was setup to only use the 2nd stage when cooling). Installer has been out 8 times in past month (no charge to us). When it's cold-below 35 or so (Ocala, FL area), we notice cold air from the vents. Installer told us we needed to check the temp above the A/H for a truer reading since we were using a laser thermo and he said we were getting the temp of the vent, not the air (we'd been better off NOT, since it showed colder temps) -- So we used a digital thermo in the duct above the A/H to measure the temps

Here are the details:

Outside temp: 28

Thermostat setting: 69

Heat Pump working: 89 degrees

"Defrost" mode: 52 to 54 degrees (this runs for 6-8 minutes at this temperature)

Thermostat (Honeywell TH6320U1000) does not indicate Aux or Emerg heat during defrost mode (we were told it WILL NOT because the compressor is requesting the aux heat, not the thermostat)

I hear a lot of clicking and noise in the A/H when in defrost mode, but I don't know how to tell if the strips are on or not. He bumped the therms up 6 degrees and the therms flashed "aux heat" and temps came out above 100 (but outside temp was now above 40 also). He just checked everything today, forced the compressor to defrost mode and said the heat strip was on and air coming out was 58 degrees (outside temp was mid 50's). ***His solution was to change out the 8kw heat strip for a 10kw (no charge to us). However, he said we had 8 gauge wire but since it already passed inspection and we had it before, it wouldn't be a problem.(we had a 60 amp breaker w/old system that he replaced with a 40 amp breaker-house built in 1998).

We're not sure we want to go this route and we don't understand why it can't maintain the current temp (even 69 out of the vent is better than mid 50's). Is this normal for this size unit/heat strip? Any help would SO be appreciated. Let me know if you need any more info.

BTW: I did a little test today also after he left. Turned on COOL (70 degrees) and checked the temp. It was 55. So the diff between cool and defrost/heat strip is only 3 degrees?? This just doesn't seem right.

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