wall programmable thermostat

[D_Hailsham]

I need to know which terminals the cables are connected to in the boiler.

Turn power OFF
Remove lower boiler cover - it slides forward.
On the right you will see the junction box. Undo the screw and it hinges down and out.

One of the brown/blue/green-yellow cables will be the main power in to L and N terminals at one end of the terminal block. The other Br/Bl/G-Y cable will be the pump, to L and N terminals at the other end of the block.

The one I am interested in is the one on the right with red, blue and yellow wires. I need to know which terminals they connect to in the boiler. They are labelled: HW; CH; CH OFF and ON.

 

[ste2466]

ok thanks i will look at lunch time today , many thanks .

 

[ste2466]

hi, the blue goes to CH ON
brown......... CH
gy.............. HW

 

[ste2466]

pi

Untitled

• ste2466
• 24 Oct 2012
• 1

 

[D_Hailsham]

hi, the blue goes to CH ON
brown......... CH
gy.............. HW

The labelling is a bit confusing. From the top they are HW; CH (ON); CH OFF; and ON. So it should read:

G/Y ...... HW
Brown ... CH (ON)
Blue ..... ON

So what do the Red, Blue and Yellow (right hand cable) connect to in this pic? I thought this was at the boiler end? I can't see them in your latest pic

Untitled

• ste2466
• 23 Oct 2012
• 1

 

[ste2466]

no this pic (the one with the red wire in) is the junction box in the airing cupboard

 

[ste2466]

i see what you mean now. the cable with the red wire in does not appear to connect directly to the boiler . all the wires that connect to the block in the boiler are brown blue and YG . it could however go to the spur swith next to the boiler and then out of the spur to the boiler but with a brown instead of red wire , if that makes any sense

 

[D_Hailsham]

i see what you mean now. the cable with the red wire in does not appear to connect directly to the boiler . all the wires that connect to the block in the boiler are brown blue and YG . it could however go to the spur switch next to the boiler and then out of the spur to the boiler but with a brown instead of red wire , if that makes any sense

Taking the spur switch off the wall will confirm what happens.

You need to find what the other end of the cable connected to HW, CH (ON) and ON connects to in the upstairs junction box.

Can you post a pic of the junction box with the cover off and identify where those three wires are connected?

 

[ste2466]

ok will do i suspet that the cable with the red wire in it as in the piture is the one that connects to the boiler

 

[D_Hailsham]

ok will do i suspect that the cable with the red wire in it as in the picture is the one that connects to the boiler

All three cables probably go to the boiler or the fused spur: pump; mains to the wiring centre; controls. It's the controls cable which is the important one - probably the red wire one.

 

[ste2466]

Hello there ,sorry about the delay in replying as i have been away. it seems the problem i was encountering was nothing to do with the thermostat or spur switch. since we last spoke i have identified that the boiler will start when the outer casing is given a little tap , it will run for approx 1hr then stop , it will not restart untill it has cooled and then will relight when given a small knock on the asing again ? regards, Steve.