Vokera gas valve.

[vdp1]

My friend has just has a gas valve replaced on his boiler and I have taken the duff one away to have a play with it as I am the curious type.

I actually found out what was wrong with it, there was a tiny brass actuator inside it that is operated by the main solenoid and this had snapped.

Anyway I pretty much worked out how it all worked apart from what does the blue thing do on it, I think it maybe a high limit switch, it is in the section of the valve that is part of the diaphragm.

[silversurfer1]

The Blue thing is the modureg its a regulator !

Once the black solenoid has opened the modureg will control the burner pressure from its minimum to maximum output. There will be a thermister within the appliance that will be connected to the electronic controls.

The controls will then alter the voltage to the modureg depending on the resistance (water temp) of the thermister when the voltage is altered then so is the amount of gas flowing through the valve.

Hope this helps

j

[johnnymiller]

Got that exact valve being replaced in mine today. Power to solenoid but no action.....

Sadly think the boiler is end of life though as a day after its been powered down water has start coming out of the heat exchanger area. As its a crappy heatline installed by previous home owner think its time to cut my losses.