Have HVAC Questions? Ask an HVAC Expert for Answers
On old Honeywell control I have 3 wires coming from gas valve marked MV, MV/PV and PV. 24v GND and 24v Hot and spark. On the new Robertshaw HS780 17NL-304A I have L2/neu, IGN x 2, L1/120 all on 120 volt side. Then on 12v side I have GND, Valve and TH. Problem I am having is cross referencing where the wire go on the new ignition control.
You need the Robertshaw 780-002 module.