My home has a 5 ton Carrier heat pump (40YR060300) that was installed in 1991. I just had it serviced and the tech made several statements that I'd like some advice on...

1. Leaving the Fan On will actually help my units efficiency by maintaining a more constant temperature mixture. I have three rooms with 25 ft vaulted ceilings (4000 heated sqft)

2. Install a "two stage heat/one stage cooling" Digital Thermostat. I purchased a Honeywell RTH8500D. I'm a EE and very versed in wiring and I wired it in myself. I'm sure the wires are connected per the instructions.

The thermostat is selected for "Multistage Heat Pump."

Question: I'm not sure I have selected the correct System. My lights dim periodically (I haven't timed it but about every 10 minutes) as though the strip heat or compressor is constantly cycling on, even when the thermostat shows "Heat On" and not "Aux Heat On". As I was writing this, the lights dimmed and the thermostat cycled from "Aux Heat On" to "Heat On". Now it appears the compressor is not running (freon pipe never gets hot.)


[Edited by keith welchel on 02-13-2005 at 09:46 AM]