new to this forum

[bobmack85]

I have a hunter digital thermostat mod.# 44860. it is controlling a heatpump ( no aux heat) It's a few years old and has worked fine.Today I switched from cooling to heat(works fine in cooling mode), but only the circulating fan runs in heat mode.No error is displayed on the screen, nor hold isn't showing. Batteris are in good shape
any help will be appreciated....thanks
Bob M

[Thermostat]

If you switch it back to cooling does the outdoor unit come on?

Have you tried cycling power to the unit?

If your system will run in cooling you could try jumpering the R and Y1 wires together at the thermostat for a test. These are the typical terminals that get entergized when the system is in heating on a heat pump system

[bobmack85]

yes, the compressor and condenser fan runs in cooling, but only the evaperater (circulating fan) runs in the heat mode. I haven't had the panel removed that houses the controls yet. but in days of yore I would take a non metallic object and push the contacter in to check the compressor. I'm sure this system has a contacter( my definination).
I will try what you suggested, and thanks

[hvactechfw]

If your system will run in cooling you could try jumpering the R, Y1 and O wires together at the thermostat for a test. These are the typical terminals that get entergized when the system is in heating on a heat pump system

Actually, O is not powered during heating on HP systems. B is powered on HP systems in heating mode for those that power the reversing valve in heating mode which is typically only Rheem, Ruud, Weatherking, & Thermal Zone brands.

[Thermostat]

hvactechfw is correct. Bobmack85 post #2 has been updated