Binding R6660D with WCH80

[Taffy45]

Hi. I'm having trouble with central heating.

Potterton Promax Combi 28 HE A.
Honeywell ST9001A Programmer.
Honeywell R6660D Roomstat RF receiver.
Honeywell HCW80 Roomstat RF sender.

Heating failed. Tried doing what i'm expected to fix, but to no avail.
The binding will not make any difference no matter how many times I try.
The receiver has picked the signal up but will not turn heating on.
Flashing red LED light when binding. Now no flashing of red LED but green receiver LED light picks up signal when thermostat is turned to put heating on.

Had it installed just under 20 months ago under the warm front scheme.

Manufactures have said warranty has expired. Although for such an essential piece of equipment one would think it would last longer than this has done.
Any help gratefully accepted.

 

[D_Hailsham]

Where does the supply to the R6660D receiver L and N terminals come from?

Is terminal L linked to terminal A or B?

 

[Taffy45]

Hi there D_Hailsham.

I'm not sure as to whether it comes from the ST9001A Programmer unit or direct from the boiler power supply. I am the tenant not an engineer so I have posted a pic to enlighten you. Hope it is of use. Thanks.

http://www.diynot.com/network/Taffy45/albums/

 

[D_Hailsham]

Looking at your pic, there is no obvious link between L and A or B, so it must be powered from the ST9001 or from the boiler.

When you are rebinding the sender and receiver, do you have to set the ST9001A to CH ON?