Nest Thermostat with Glowworm Betacom 30C

[Chris298]

Morning all,

As above I am wanting to fit a Nest to my Glowworm Betacom 30C.

I’ve read a very helpful post on here which says I can take the Heatlink and put 230v in to its L & N, and then using the 24v connector block on the boiler, wire that in to the 2 & 3 on the heat link.

That sounded great until I read the manual for the boiler where I found this under 10.2.

I was going to go and pick a Nest up today but this has stumped me a bit.

Under 10.3, it says a thermostat using mains voltage can be attached at a different plug in the boiler, however this method is slightly more complicated.

Hope someone can help, thanks in advance.

Chris

 

[stem]

The L and N supply to the Nest are there solely to provide it with operating power.

Terminals 2 and 3 are a connected to a voltage free switch. These terminals are not connected to the 230V supply in anyway. So terminals 2 and 3 will switch whatever is connected to them be it 24v or 230V. So what you propose below is fine:

I can take the Heatlink and put 230v in to its L & N, and then using the 24v connector block on the boiler, wire that in to the 2 & 3 on the heat link.

When using 24v what you must not do is connect any of the other Heat link terminals to L. You will sometimes see instructions to link terminals L, 2 and 5. That is only for 230V switching and for obvious reasons must not be done when using 24v