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Discuss Thermostat no display in the Plumbing Forum | Plumbing Advice area at PlumbersForums.net

Sorry if I seem like a novelist as I am but just seeking a little advice as I went to turn on my heat 2 days ago and noticed I had no display on my thermostat but my heat was turning on. So after checking the breaker, the batteries, making sure the door on the heater was on correctly and changing the thermostat with another one, which didn't require batteries but needed me to hook up the C wire which I found behind the wall and hooked up, I'm still having the same problem and wondering if anyone has any suggestions of what to check next? Thanks
Here's a picture of how I have it wired now with the top blue wire hooked to C then Green to G then Yellow to Y then Tan to O/B then Red to T which where the same way on the old thermostat except for the blue C wire I found tucked beneath some paneling not hooked up I thought needed hooked up as this thermostat doesn't require batteries but the old one did.


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I'd find it helpful to know the make/model of both the old and new thermostats.

It's bad practice to leave redundant wires connected at one end and free at the other. So, I would expect that the blue netural (I guess but needs checking) wire needs to be reconnected at the boiler end as well.

As @exedon2 implies, if you need some bloke on an internet forum to point this out you should probably get a heating engineer to sort you out. If you make a mistake you can cause significant damage to your boiler, or worse, yourself.

Be safe.

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