Question about GE Zoneline AZ55H09D Air Conditioner

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Temperature varies 13 degrees around setpoint on aux heat

When outside temperature drops to the point where the auxillary heating elements come on, the temperature in the room will vary 13 degrees. Foe example, with the thermostat set for 70 degrees, the temperature in the room will vary from 66 degrees to 79 degrees. This is unacceptable for comfort. I had a GE technician come out last December to service the unit and he replaced a number of parts, but the problem still exists.

The problem is only this severe when the unit is on auxillary heat. Even on normal heat pump heating, the temperature variation is about 5 or 6 degrees.

This Zoneline replaced an 8 year old Zoneline AZ51H09DBC the performed just perfect....temperature on all seasons and operating mode controlled temperature within about 2 or 3 degrees.

Since my previous Zoneline worked fine in this room, does anyone have any ideas why this new unit has such a large hysteresis in controlling the temperature around the set point?

Any help will be appreciated. I very disappointed in the unit and in GE's inability to fix it.


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Re: Temperature varies 13 degrees around setpoint on aux...

I don't have the book for this particular unit but, check the sequencers that control the electric heat mode, as the regulator heat pump works good. The part may have a time or temperature delay that is too long for you. Also if it has a remote thermostat, check the heat anticipate setting. You will have to check the installation manuel, but its usually .6 to .8, but I don't think that is the problem.

Posted on Dec 04, 2007

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