To give you a little more insight to the problem: 1) We have a Bryant 1-stage, hybrid system. 2) It is set, per installer, to utilize heat pump, until outside temperature drops below 35 degrees, & the heat pump can no longer bring home to desired temp. 3) at that point, the propane burning portion of the unit should kick in, i.e., the propane is set to function as E-heat. 4) If the propane portion does not kick in, after 3 attempts or so, the unit shuts off. If the outside temperature comes up above 35 degrees, you can reset the outside breaker for the unit & the heat pump will function, again, until temp drops. The installer/repair person has been out several times over the past several weeks, and can "somehow" force the propane unit to light & work short term; however, when the unit goes (due to increased outside temp) back to heat pump, the cycle described above repeats itself with propane not kicking in, when temp once again drops, as it should. THINGS THE HVAC PERSON HAS TRIED THUS FAR: 1) cleaned the unit twice & restarted each time, (& he reported according to code readings he did the following): replaced the burners, the orifices and the exchanger; each time, he restarted the unit & pronounced it fixed. His most recent visit, today, he advised he thought we should contact the propane company, since he suspected we had moisture in our tank. I called our supplier, Southern States, & explained the serviceman's thoughts. Southern states advised they put additive in each & every tanker of fuel they received & this would alleviate any problems related to moisture in any individual tank. The HVAC serviceman seems to be at a loss at this point & meantime, we are spending mega dollars trying to heat with kerosene space heater & small electric heaters
. Where should we go from here?