Faulty boiler thermostat

[Paul17088071]

Looks the correct head to me, you will need to line up the flats on the spindle (brass bit) with the flats in the actuator. Sometimes moving the actuator manually (plastic lever on the end) helps.

thanks for your response.

Looking at the flats on the actuator and the spindle, they don’t seem to match up. Am I doing something stupid (most probably )

Are you advising to manually pull the spring whilst on the valve to match up the flats with the spindle?

Thanks

 

[Stuckinarut]

Are you pushing the black tab in located on the side?

 

[Paul17088071]

Are you pushing the black tab in located on the side?

Sorry, do you mean one of the blue or red circled below? If this is the case, I haven’t tried that.

Many thanks

 

[Stuckinarut]

Sorry, do you mean one of the blue or red circled below? If this is the case, I haven’t tried that.

Many thanks

View attachment 376973

The one circled red, if you look at the bit circled blue when you push it (circled red bit) you should see it move.

 

[cross thread]

Manually move the brass base spindle to match the position of the valve

 

[Paul17088071]

Also check the brass base valve turns easily

Thanks. Should this valve turn all the way around, as it only seems to move a slight turn in both directions?

Thanks

 

[ericmark]

Hope you now have the valve fitted. However, there should be both a wall thermostat which moves the valve, and radiator thermostats (TRV) the latter should have stopped the house over heating even if the motorised valve stuck open.

Also, the motorised valve head should have turned the boiler on/off even if not connected to the valve.

 

[Paul17088071]

Thank you for your advise, we were turning down the TRV valves to reduce the heat in the house.

The boiler was definitely turning on so the motorised valve was working. I’ve just reattached the head to the valve, and so far so good, the hot water demand is on, and the radiators aren’t hot

My second test I turned on both the heating and hot water demand, but the spring move to the H position, should this have moved to the M position?

I’ve now turned the heating off and it’s stayed on the H, is this normal? I know someone previously mentioned it may stay in last know position so hoping this is the case!

Many thanks again

 

[cross thread]

Correct ,sits in last position ,it may have gone to H as the hot water was up to temperature , mid position if both heating and hot water calling

 

[Paul17088071]

Correct ,sits in last position ,it may have gone to H as the hot water was up to temperature , mid position if both heating and hot water calling

Thanks for clarifying. It seems strange as you’d think if it’s set to H the hot water would still continue to flow through. I’m sure there is some science behind it