Main Eco Elite no CH but HW OK

[Mark13]

Hi,

My boiler just stopped heating Today. As mentioned hot water is there, I also hear the pump working. I have a simple mechanical thermostat on the wall but turning it on / off does nothing - I don't hear the diverter valve motor triggering. The CH demand light is off, no error is shown. Any ideas how to test if the issue is the room thermostat? (not sure how the wiring is done there)

Regards

 

[JohnD]

Photos of the thermostat and your timer/programmer would help.

It isn't a wireless stat, is it?

 

[Deleted member 267285]

It isn't a wireless stat, is it?

I have a simple mechanical thermostat on the wall but turning it on / off does nothing

 

[Deleted member 267285]

@Mark13 - do you have any test equipment? If not turn the power off and join your switch wires together and safely turn power back on.

 

[JohnD]

@Mark13 - do you have any test equipment? If not turn the power off and join your switch wires together and safely turn power back on.

Unless it has a neutral.

 

[Mark13]

Yes it's a wired thermostat. Just unscrewed it and it looks like this:

Only yellow and red wires connected to thermostat, and ground to the box. So just short y+r?
Timer on boiler is set to constant heating.

 

[Mister Banks]

Yes it's a wired thermostat. Just unscrewed it and it looks like this:
View attachment 327432
View attachment 327433

Only yellow and red wires connected to thermostat, and ground to the box. So just short y+r?
Timer on boiler is set to constant heating.

What’s the blue wire doing? It looks like it is just resting against the metal box which is earthed.

 

[RandomGrinch]

So just short y+r?

Yes, as @CBW says, isolate the boiler power, then connect the red and yellow wires together in the same terminal.

 

[RandomGrinch]

What’s the blue wire doing? It looks like it is just resting against the metal box which is earthed.

It looks like it has insulation tape on the end to me?
It's not ideal, but there's no saying it is actually connected to anything at the other end of the cable!

 

[Mister Banks]

It looks like it has insulation tape on the end to me?
It's not ideal, but there's no saying it is connected to anything at the other end of the cable!

It may not be connected at the other end but equally it might be, just something I would check.

 

[Deleted member 267285]

Unless it has a neutral.

Won’t matter as it has the same effect as turning the thermostat up.

 

[JohnD]

Won’t matter as it has the same effect as turning the thermostat up.

You surely don't mean that if the thermostat cable provides
LIVE
NEUTRAL
SWITCHED LIVE
you can connect them all together.

 

[RandomGrinch]

You surely don't mean that if the thermostat cable provides
LIVE
NEUTRAL
SWITCHED LIVE
you can connect them all together.

Uhhmm...

If not turn the power off and join your switch wires together and safely turn power back on.

Perhaps, it could have been put better, but there is no mention of connecting a neutral...

 

[JohnD]

... there is no mention of connecting a neutral...

Here.

Unless it has a neutral.

Won’t matter as it has the same effect as turning the thermostat up.

 

[RandomGrinch]

Here.

Apologies to the OP, but I'm afraid I'm not getting your point?
Chris has suggested connecting together the 'switched wires' in the thermostat - in this case the red and yellow.
Where does the thermostat having neutral or not come into this?