siemens RDJ10RF RCR10433 issue

[Johnnylate]

Morning. Our central heating is controlled by a Siemens rdj10rf going to a rcr10433 receiver. We have had issues with the controller before but the last three mornings, the receiver has been flashing red yet the controller appears to be working fine. it even goes off during the morning and comes back on in late afternoon as per its settings, overnight is the only issue?
I can't see any obvious reason why this is happening.
I suspect I need to replace both but dont want to do this and find the fault is elsewhere?
I appreciate any help

 

[Echo the husky]

These stats are awful, they are known to be unreliable. Replace the lot with something from Honeywell.

 

[bazdaman]

Plus 1

 

[Johnnylate]

I think you are probably right but I'm concerned there's something else wrong and about to start spending and finding I'm not fixing anything. It's now getting worse, not just not coming on, it's turning off while on.
We had three power cuts two days ago, electricity board were working up the road from us and this has started since then...I'm starting to sound desperate!

 

[Echo the husky]

I'd be more surprised to find one of these stats was working properly. They are usually faulty after about a year or so, it was quite common for them to be faulty straight out of the box...

You can easily prove most of the heating is working by turning off the mains supply, open cover to Siemens receiver, join the wires that are in terminals LX and L1 into the same terminal, put cover back on. Turn power on and heating should run forever. If it does the stat is faulty. You can try resetting the 2 units and re-pairing them again, but I've never had that make them work again.

 

[Yellow134]

Hi. I have just started having problems with my siemens RDJ10RF sender unit - it is set to come on in the morning 4 an hr & back on in the evening as per program. Just today it's not coming on automatically as it should. Have overridden the sender unit & all works well (heating comes on)...any advice ?