SALUS Model ST620RF not working, light stuck on a dim red

15 Jun 2023
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New Zealand
I have an issue with my Salus thermostat (model ST620RF). All of the sudden, the lights on the receiver have gone blue and red (dimmed) and the heating and hot water stopped working. The thermostat has new batteries and is working fine as well. I have tried multiple times to re pair it and reset it but none of that has worked either.

Any ideas what the problem could be? Its getting to winter where I am and no heating or hot water is not very good for us lol and the Salus support team are no help at all. Thank you! I have included some pictures of the units, the dark picture shows the state of the lights that I mentioned above (no solid light very dim)


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I've not come across this particular combination of faults before, especially the dim lights. However, under normal circumstances I think that the red light usually means it is in 'Sync' mode and trying to communicate with the thermostat, and blue means the thermostat is calling for heat.

the heating and hot water stopped working

This bit is odd, because the Salus is a room thermostat, so only designed to provide control for central heating. It does not have hot water control functions. So, if you don't have any hot water it would appear that something else could be amiss. Does the receiver have mains power? Check everything is switched on. Has someone turned the boiler off at its isolator?

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