CH & DHW switching issue

[condeh]

Ok, I am working through the diagram now, so far, found no mis-wiring, so far as I can tell.

Tracing the 'black' wire shown on your diagram entering block 4, is running as shown from the programmer CH ON terminal. When I then turn CH on on the programmer, should that not be live? currently, it will only go live if I cycle through the HW on-off procedure as described earlier.

Would this suggest it is the programmer itself interfering in proceedings?

 

[condeh]

Right, another update.

I have traced everything out as per the wiring diagram you enclosed, and it is correct. I have two questions though.

I also have a CH Off output from the programmer, but there is no wire from that terminal. As it is not included in your diagram, I assume this is not important, but wanted to check.

The only area I'm not 100% on is the wiring to the room stat. I have a BR1 receiver, and I'm not sure how terminals 1, 2 & 3 on your diagram correspond to my options of L1, LX & L2.
Currently the CH On wire runs from programmer to block 4, then out to LX, so LX='1' on your diagram.
L1 then runs down to block 5, and is shared with the white wire from the MPV, so L1='3' on your diagram.
I can't find a wiring diagram/instructions to confirm the BR1 is correct.

Many many thanks for all your time and effort thus far.

 

[Blagard]

Ignore CH off - it is not used

You receiver will have a permanent live and neutral supply so know where they are then ignore them. Because you want the two contacts that switch demand for heat on/off. According to you these are terminals LX and L1

It should be easy enough to test the receiver.
Put the CH on then off

Disconnect and check that the cable to LX in the Receiver is live then off respectively with putting CH on and off, so you know for sure that cable is your CH on. Re-connect after testing

Then with CH on adjust the thermostat to see is L1 is switching on and off as you call for heat or not as the case may be.

It may be that if the receiver is not operating correctly L1 is never being switched on. If that is the case you need to trouble shoot the thermostat. Perhaps reset it.

If you can, photograph the terminals in the receiver so that the they can be clearly read. Unfortunately I am unable to find an online copy, hence the request.

 

[condeh]

Lx does not go live when I turn on the CH until I cycle through the HW, it does stay live then, even when HW is put back to off.

I have retraced the wire to Lx and it is in a block with the wire which leads to CH on at the programmer, nothing else.

L1 does go then live when I operate thermostat, MPV moves to H.

 

[Blagard]

Go back and do exactly as I said, disconnect the cable to LX and test the
cable is becoming live when you put CH on! if it isn't then it is not the "CH on" cable or your programmers CH terminal is not live or someone cut the cable! It is one of those three possible faults.

Edit you may have more than one problem but you need to tackle them one at a time hence the above.

 

[condeh]

I did, sorry for not making that clearer.

With HW and CH off, and Lx disconnected, the Lx wire is off. When I turn on CH, the LX wire remains off. When I turn on HW, the LX wire remains off. When I turn off HW, there is an audible click from the programmer, and the Lx wire now goes live.

 

[Blagard]

<snipped>When I turn on CH, the LX wire remains off.

So please check that the programmer CH terminal is failing to go live with CH on? - That simple! it is supposed to be 100% independent of the HW controls

Because it sounds like your programmer is faulty.

 

[condeh]

I tested that connection earlier, it will only go live once I cycle the HW controls, so it does seem to point to a dodgy programmer.

I assume there is no way to link the programmer out so to speak, to test this theory?

Thanks again.

 

[Blagard]

You could wire the "CH on" cable to the same terminal as the "HW on" That should give you both on together using the HW side of the controller. Your MPV should then go to the middle (keep stats turned up when checking)

Just make sure the HW terminal does go live when on

 

[condeh]

Apologies for long delay, I was away.

New programmer arrived and fitted. All problems solved.

Many Thanks to all.