Gas Furnace (58MVB100-20) Fails To Start

[Lucas4]

My new furnace (and heat pump) was just replaced because of a sizing problem. The dealer's son failed to check the gas furnace to see if it will start. A few nights ago, the furnace attempted to start when it got too cold in the middle of the night but FAILED TO START. I have a heat pump with gas back-up (Hybrid System). Ignition fault (FN 34) and Ignition Lockout (FN 14) appeared on the User Interface. I informed my dealer. He is yet to come by.

Question 1. Page 44 of the 58MVB Manual talks about STEP 3 ( Prime condensate trap with water) and STEP 4 (Purge gas lines) - could they be the problems since the installer didn't do anything like that?

Question 2. Since the puron for the heat pump was weighed in when it was cold outside, does the pressures and temperatures need to be checked when the outdoor temp is, say 70 deg?

Thanks,
Lucas4.

[air2spare]

make sure the gas supply is turned on at the unit then kill the power to the unit and then turn it back on, it will clear the fault code and try to light. If that fails try again to give it a chance to clear the air from the gas line

[mwjhvac]

Also take the front cover off and check to see if the switch on the gas valve is on. Seen this many times.

[air2spare]

Also take the front cover off and check to see if the switch on the gas valve is on. Seen this many times.

good point...I've seen that most often