Came out to investigate a no heat. I cycled the furnace and the igniter would glow, but the burners wouldn’t ignite. It tried again and the burners stayed lit for a second before kicking out. On the third attempt, the furnace ran fine for five minutes. Error light flashed six times indicating a flame failure. I cleaned the flame rod and checked the igniter, everything was okay. 24v going to the gas valve. I tapped the gas valve with a screw driver to loosen up any stuck bearings. It seems like the gas valve is starting to become faulty. For safe keeping, I cleared the drain and pressure hoses and checked the pressure switches and venting, all was clear. They said they will monitor the situation between now and the cleaning.