Worcester 35CDi II Thermostat problem I thought :(

[Infinity]

Hi,

Sorry I'm not very technical.
I have a Worcester 35CDi II combi boiler connected to a Drayton Digistat +3 wall thermostat. I've always used the digistat in manual mode, so set a temp and let it come on and off throughout the day. But a few days ago it stopped working. When I put the temp up on the digistat the little flame comes on the digistat but I do not hear the click that normally comes on from the digistat to turn the heating on the boiler. There is no red light for the heater and the flame red light indicating it heating. so....

I disconnected the digistat and connected the two wires coming from the boiler to bypass the digistat and the boiler came on. So I thought it was a faulty wall thermostat and ordered a Drayton Digistat +3 .
When the new thermostat arrived I swapped it out, but it still does not work! Not sure whats wrong. Could it be another faulty thermostat? Is there a problem with my boiler?
I'm going to buy a non digital basic thermostat tomorrow to test.
Oh I forgot I cant get the built in timer to work wither on the boiler.

Any help will be appreciated.

 

[ollski]

Is this the wireless thermostat?, have you tested the receiver?

 

[cross thread]

its the receiver lots for sale on ebay

 

[Infinity]

Is this the wireless thermostat?, have you tested the receiver?

No a wired one thermostat with batteries for the display.

 

[Infinity]

its the receiver lots for sale on ebay

Not a wirleess one

 

[ollski]

integral timer has probably been disconnected and replaced with this as its knackered, but you could try plugging it back into the pcb. Are you sure the new one is wired correctly?, almost certain it wont be faulty

 

[DP]

Has it got two pumps, two circuit boards ?

 

[Infinity]

integral timer has probably been disconnected and replaced with this as its knackered, but you could try plugging it back into the pcb. Are you sure the new one is wired correctly?, almost certain it wont be faulty

I'll have a look in the boiler and try to locate the integral timer. Is it easy to replace?
The new room thermostat has two wires, it exactly the same make and model as my older one. I just swapped the two wires over (brown on the top connection and blue on the bottom)

 

[Infinity]

Has it got two pumps, two circuit boards ?

Its got one pump as far as I know. I've not taken the front off to get at the circuit boards yet but will check tomorrow.

 

[ollski]

i would sat at least 3 wires for the hard wired version, permanent live, neutral and switch live to boiler

 

[Infinity]

Sorry it has 3 wires. The brown and grey have always been connected. There is a black one but that's never been connected. This setup worked for over 9 years. I've take a pic of the connections. I've put the grey and brown together to get the boiler to work. I have not connected the rest of the thermostat.

 

[Johnmdc]

When you fitted the new stat did you change the back plate as well? If not then do so, that orange box on it is a relay that could have failed. (That is what you should hear clicking when you turn it up and down)

 

[Infinity]

When you fitted the new stat did you change the back plate as well? If not then do so, that orange box on it is a relay that could have failed. (That is what you should hear clicking when you turn it up and down)

The back plate was changed too.

 

[DP]

Has it got two pumps, two circuit boards ?

Its got one pump as far as I know. I've not taken the front off to get at the circuit boards yet but will check tomorrow.

Don't bother with that OP
My comment has no relevance to your quest

 

[ollski]

Have you refitted the old one again?, the digistat in your pic is 6 years old