My 1990 Carrier 58PAV075-JC doesn't turn on. I have a Carrier model # 58PAV075-JC (---product # 58PAV075-111JC). The unit is not turning on. I see that the ignitor piece glows bright orange, but I dont see/smell gas going in (missing the hissing sound and blue flames). I'd opened up the unit and there is a self test procedure sticker. I had touched the 2 terminals and the unit cycles through its fan, ignitor, relay, blower etc. I'd even took the cover off for the control board. The 3 amp fuse looked good. I then tried to measure voltage at the blue wire (going into M1 terminal) and brown wire going into C2 at the gas valve. There isn't any voltage at all. I'd used a multimeter set on auto Volt and measured across both terminals and even from each terminal to ground..still no voltage. I got 90 ohm resistance measuring the 2 prongs in the switch at the gas valve. I suspect the relay for the gas valve is bad because when I jumped 24 volts to the gas valve manually, it opened. Is it possible to buy just the relay or do I have to buy the whole board. Please advise and thank you in advance.