Thermostat White-Rodgers 1F82-261 switches to stage 2 heat for no apparent reason

Question

I am running a central heat system that uses a heat pump as stage 1 and a gas furnace as stage 2. The thermostat used is the White-Rodgers 1F82-261 which supports 2 stages of heat.

When using regular heat mode on the thermostat and setting the temperature to 1 degree Celsius above actual temperature, I noticed that the thermostat was consistently switching to stage 2 heat after about 10 minutes running the heat pump. The manual of the thermostat mentions that stage 2 should only be used when the set temperature on the thermostat is 4 degrees above the actual temperature.

Is there another reason why the stage 2 would kick in prematurely? For example, I suspect that my ventilator is not pushing enough air for the heat pump and therefore may require lots of time before an actual temperature increase is noticeable. Would that be possible that the thermostat triggers stage 2 if no temperature increase is noticed for 10 minutes? There is no mention of that in the manual though.

Answer 1

Some digital programmable thermostats are intelligent in that they determine the best way to get to point X in X time, I had a fellow who set his thermostat for X degrees at 6 am and he heard the furnace kicking on earlier than this time sometimes as early as 430 am. I checked out the thermostat and found it had something called "adaptive recovery" that determines the best way to reach the temperature setpoint without using the heat strips which is 2nd stage heat, this involves running the unit before the time set to most economically reach the setpoint at the time programmed, in other words it starts early to actually be at X temp at 6 am not start heating at 6 am. Since it ran before and still does other than this 2nd stage initiation it is the thermostat doing this most likely, I would thoroughly read your thermostats programming instructions or call the 800 # for the manufacturer of the thermostat, it is very likely doing what it is set up to do and there is nothing wrong.

Answer 2

I didn't look up the manual but it is very possible that it kicks in second stage after a set amount of time. There should be a installer configuration section where you can adjust those settings.... Now I'm curious, I'm going to look up the manual.