i had my install started today. they are coming back monday to finish. i got a 70,000 but 95% goodman furnace with a goodman 3 ton seer 14 heatpump r410a. i want to know if what they are doing is ok. they put a fossil fuel kit on it. my new thermostat is a white rodgers model 1f95-1277 ( a touch screen) and in the book that came with the thermostat it said you dont need a fossil fuel kit. is it ok to still use the fossil fuel kit?