1018 igniter on intertherm mmha-05 furnace

nascar46747

inducer motor comes on igniter comes on but only 14 volts to gas valve witch they say that’s normal until it calls for gas , does not have pressure switch does the inducer motor control the gas valve after going threw the 1018 igniter

EBEBRATT-Ed

The inducer if it does not have a pressure switch there could be a proving switch inside the inducer motor. See how many wires go to the inducer motor. If it has 4 the motor probably has a switch inside.

The ignitor has to prove the pilot is on before the main valve lights, but it does it indirectly through the gas ignition control or circuit board. Or you could have hot surface ignition

nascar46747

I do have 4 wires coming from the inducer motor two red and two black how can I test them to see if it is telling the 1018 igniter board to turn on gas valve I got a different board but it is doing the same thing thanks jim

EBEBRATT-Ed

The centrifugal switch in the inducer motor is the two red wires. You can disconnect them and put an ohm meter on those two wires it should be open circuit with the inducer off and closed when it runs.

If you don't have a meter you can try jumping the wires together. Do this as soon as the inducer starts. use caution

Do NOT run the furnace with the jumper in place Carbon Monoxide can kill.

Look at the furnace wiring diagram.

nascar46747

I have a ohm meter thank you I didn’t want to burn anything up will give it a try thanks again jim

nascar46747

I tested the inducer fan it is open and closes when fan starts up any other ideas before I buy a control board supposed to get 20 below with winds tonight was hoping to get it going but doesn’t look good thanks jim