20 yr old gas furnace shuts off burners after ignition very intermittant
 

Furnace shuts off burner with no warning every three or four days. It shuts off the gas to the burners. The induction blower keeps running and the pilot stays lit. To get it running again, I shut off the power, turn the knob on the Honeywell VR8440 to the off position. Wait several minutes, turn the VR8440 knob to the on position and turn on the power. It comes back on and runs normally for three or four days. The day before this problem started every time we used the gas range the flames were totally yellow. Later that same day they were blue again. Could the gas company have had either dirt or moisture in their lines that is affecting the Honeywell gas control ?

i got similar issue. pilot is lit, but cold air is blowing.. seems like gas valve is not operating properly... or thermocouple (if its there). so, what did you find out?

You can have your gas supplier check the incoming pressure first, be that natural or LP to see if a regulator is sticking, then if that checks out you should have your home gas system checked out by a professional. There may be a restriction somewhere in the supply piping or a valve problem. If you haven't had your furnace cleaned regularly, (every year for me) you should have the entire system cleaned, starting with ducts and ending with the air conditioning condensor coils and drip pan. I hope this helps you solve your problem.

vent on gas meter could be icing over that might be why the flame improved later in the day when the ice thawed .check to see if water is dripping from the roof onto your gasmeter