If solenoid valves are malfunctioning dangerous pressure might build up and cause damage.
Testing furnace gas control valve.
If the appliance is a boiler or furnace it ll use 24 vac to operate the main valve.
The following steps will show you how to troubleshoot gas control valve solenoids.
Pull the wires off.
Wait for the unit to cool if it has been in use.
Set the thermostat or the device s controller slightly above the current room temperature.
Check to see if you re getting 24 vac at the terminals on the gas valve.
Testing gas pressure at the valves is often the first thing hvac technicians do when they are called in to check on faulty furnaces.
Turn off the gas supply valve to your appliance to test whether your valve is capable of shutting down properly.
Standing pilot gas valves.
I will be checking various gas valves to see if you can check the continuity of the solenoid with an ohmmeter.
The difference is the standing pilot gas furnace always has a pilot light on.
There are four possible reasons for solenoid valves malfunction.
Step 1 check for coil burnout.
The ignitor will be 120 volts the gas valve is most likely 24 see if your transformer shows voltage on the secondary terminals.
Turn off the gas feed line valve to the dryer.
Some gas valves cannot be checked with an ohmm.
There should not be a flame up there if the valve is working correctly.
Turn off the furnace at the wall control.
How to check the furnace gas valve with a multimeter step 1.
Locate the front lower access panel to the appliance.
Take out the bolts in the service panel on the side of the furnace using a nut driver.
If replacing the thermopile doesn t work then you need a new gas valve.
This valve is usually found in the wall line leading to the dryer and is shut off by turning the handle perpendicular to the gas line.
Everything that applies to the electronic ignition sequence of operation by the way of the safety circuit must be proven before the gas furnace will allow the gas valve to fire the main burners to provide heat.
Most gas dryers have pullout snap panels.
Adjust pilot flame as necessary to make sure the thermocouple is getting enough heat.
Locate the gas valve.
Coil burnout failure to open failure to close or solenoid valve noise.
Standard solenoid valves are used for pneumatic gases.
Even though these systems are generally built to last gas furnace valves are the parts more likely to need replacement over the life of the furnace.
