New stat to replace honeywell T40

Ah! Because I attached the wrong photo the original honeywell wiring was/is

Blue 2
Black 3
Brown 1

So yes this does mean I wired the honeywell wrong once and took a photo of it.

Go me!
 
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Got another one, still dosn't work. Wondering if the boiler isn't giving it enough power?
 
Just to confirm, this is the CORRECT working wiring for the T40.

I've searched, I've looked at other threads on this forum, all say the same and I've done exactly the same. I just don't understand why it won't even power on!
 

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Time for testing equipment really.
Right!

Got a multi meter and checked I was using it right with known battery voltage (fully charged 9v and 1.5v).

I'm getting 100v out of live which is likley why the moes is not powering up.

The question is... Why? Is this normal lol
 
What are you testing between? Not normal for 230/240Vac supply, no.
 
I was testing between live wire (brown) and Neutral (black).

Tried live to blue too just to make sure.
 
I was testing between live wire (brown) and Neutral (black).

Tried live to blue too just to make sure.

Is this with the Honeywell attached, the Moes, or just the wires? Sounds like there’s a loose connection somewhere, or your boiler isn’t producing the live out properly.
 
Just the wires, I turned off power, undid the wires, left them exposed, turned power back on and tested, just over 100v.

Boiler is <1 year old
 
Does the Honeywell go to a spur, or the boiler?
 
Just been up in attic and traced the cable from the stat.

The white cable in the image is from the stat, the grey goes to main power.
 

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Boiler is <1 year old
You may have damaged something internally.

Ok, unless this wiring changes anywhere:
blue is neutral
Black is live out
Brown is live return (switched live).

Test between neutral and black and report voltage

Once all this is done, you will need someone to check your front boiler case seal is on correctly.
 
Right. I tested as suggested and getting just over 100v. With the moes connected, when I touch the screws between L and N I get 115v.

Moes box states 95-240v so it should work. Maybe it's duff!

What a kerfuffle!

I text the plumber who installed the boiler and he says he has no idea why it's 100v and not 230v.

So! I went to the boiler and tested the contacts from mains power coming into the boiler, that returned: ~100vac

When I tested the "outbound" to the thermostat, I got: ~100vac

♂️ Either way the moes should work with my 100 volts according to the box.

Mumble grumble
 

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