Heil Gas Furnace: NULK Re: Burners Won't Ignite These furnaces use a Hot-Surface ignition control for ignition (GHAC replacement = IGN.02). Qty Possible Causes: 1 Bad Ignitor Bad Gas Valve Pressure Switch Open 1 Rollout Limit Tripped Bad...

ICP/Heli Gas Furnace: NULK Re: Burners Cycling Off / Burners Won't Stay On The furnace burners fire and runs, then the burners shut off and the furnace goes through another ignition sequence. These furnaces use either a hot-surface ignition controller. (A common replacement control is the...