Baxi Main Eco and Nest 3rd Gen wiring

29 Dec 2021
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United Kingdom
Hi all, im a going to replace my PROCOMBI CT Plug in Wireless 24HR DIAL Thermostat with a nest 3rd Gen Thermostat. But I'm a bit confused to how best to do this. The image attached is how the old receiver is wired at the min. Can someone advise if they had done one of these before and the best way to wire the boiler to the nest heatlink? any pointers will no doubt help speed up the process ha ha!! thank you


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I may be very wrong, but I would have thought using the OpenTherm connections on the far right, would give you the best results! :)
Thanks RandomGrinch much appreciated. That's what I'm going to use as have been doing further research...fingers crossed it works as have read that some baxi boilers don't play nice on OT with Nest systems.
The only other point to note is ideally, the mains power for the Nest heat link, should come from the same connection as the boiler. Turning off the power to the boiler, should also isolate the Nest; for the protection of anyone working on the boiler.

I hope that makes sense!
have read that some baxi boilers don't play nice on OT with Nest systems.
It's always good to know that an open 'Standard', isn't always standard! :D

Good luck :)
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