Gas Fryer #4 vat not heating, examined unit, opened control panel, checked wires and interface board, all LED lights coming on - checked drain switch opens/ closes okay, have 24v to gas valve, pulled spark wire and confirmed unit getting spark - gas valve not opening, will order disabled unit until parts arrive. 12/17/19 Went to change #4 gas valve, found 2 hoses for gas, right side was off, turned on and cycled, #4 now working - customer stated #1 is popping, relay okay, blower dirty, cleaned vent and replaced both ignitors, no more popping.