We have a Honeywell Thermostat T8112D1005 (1) 0014 PF1A. It is about 10 years old. In the morning the heat does not kick in, but if I manually flip the furnace circuit breaker off for a few seconds, then on, the furnace then works fine. What is causing this?

Exact brand and model number of furnace?

Honeywell Thermostat T8112D1005 (1) 0014 PF1A.

Hello?? The Furnace brand and exact model not the thermostat model.

Here is your thermostat manual

http://customer.honeywell.com/techlit/pdf/PackedLit/69-1633.pdf

I'm sorry, I misread your response. Carrier Multipoise, Condensing (LP Gas) Furnace,
Model # 58MXA 120-20.

The furnace may be malfunctioning/locking out, and interrupting/restoring power cancels the lockout. Look for a status light on the front/blower panel. If blinking while heat is not working, check/read the "SERVICE" label.