Betacom 24 and wiring in a wireless stat

[dav123a]

Current boiler has no stat of any kind. I've got a honeywell wireless stat to fit but I'm not sure what the connections are in the pcb. The boiler was put in around 2007 . I think the connections are either 3,4,5 . But there is already something in these going to the pcb. Or it could in place of a small length of cable that is the marked room thermostat that was coiled up behind the pcb. Can put a pic up if needed. I'm hoping someone can help as I'm slightly baffled by these connections.

[silversurfer1]

There are a number of different beta com models so the Gc no would help. from memory there is either a 24v low voltage connection on the left hand side of the pcb housing. If you are using a 230 VAC room thermostat then you need to cut the link on thermostat connection and fit a terminal block to it, just googled it and the model I'm looking at says its terminal x20 for 230VAC connection

cheers

ss

[dav123a]

It's a honeywell cmt927 I've got . There is a timer on the left hand side of the board that's mains powered. Is the room thermostat cable just that , a short and it turns the heating on ? If so I take it I can connect to that and in effect the the wireless stat takes places of the what's there now. My concern has been getting the right voltages and could have a go but I'd rather not pop a pcb.

[dav123a]

Gc number is 47-019-04

[LookAtMyCat]

It's the M7 block, the 2 connections above the power block. If you've got an integral timer it'll be obvious because they'll be linked out.

[dav123a]

Cheers does it need a volt free closed contact to turn on or is there a voltage needed ? I'll have a look in the morning and see what's in m7.

[LookAtMyCat]

Yes. If a boiler has 24v thermostat contacts they will be usually be linked out if not wired to. They just go to A+B on the CM927 receiver, any way round. I usually run 4-core from the boiler to the receiver; job done.

[silversurfer1]

A&B on the cm927 X17 volt free on the boiler

ss