4 wire thermostat to 3 wire!
- Thread starter sakm
- Start date
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ok it’s just possible the new thermostat is faulty but try moving yellow back to terminal 3 and give it another go.
Do you have a multimeter?
Do you have a multimeter?
Well I'm getting somewhere!
The live and switched live are the wrong way round! The wife never helped the situation by turning the heating off on the programmer!
Swapping red and yellow on the new stat makes the heating work as it should off the stat
New problem! With the hot water off on the programmer the led is on on the stat bit very faint with hot water turned on whether calling for heat or not the led is off
The live and switched live are the wrong way round! The wife never helped the situation by turning the heating off on the programmer!
Swapping red and yellow on the new stat makes the heating work as it should off the stat
New problem! With the hot water off on the programmer the led is on on the stat bit very faint with hot water turned on whether calling for heat or not the led is off
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Can you post photos of the wiring centre?
I can indeed but be warned its a bit of a mess if you ask me!
I did draw a diagram with paint to make it easier I have attached it to this post
I have included a wiring diagram from the boiler too (ideal logic heat 15)
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You are right about Yellow being Live to the Thermostat. Overall the colours of wiring in use are confusing and the wires could do with some coloured insulating tapes to identify each end. You wouldn't normally expect blue and yellow/green wires to be at 230V unless clearly identified as potentially Live.
Hard to tell from the photo but is there a blue link between 2 & 8 so the valve and room thermostat get a Neutral connection from 8.
Hard to tell from the photo but is there a blue link between 2 & 8 so the valve and room thermostat get a Neutral connection from 8.
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Yeah I spotted it and just been up and double checked!
I have heating and hot water again and the stat works but for some reason the LED is illuminated occasionally.........all the time if the hot water is off on the programmer!
I have heating and hot water again and the stat works but for some reason the LED is illuminated occasionally.........all the time if the hot water is off on the programmer!
The indicator lamp on the room thermostat?
That's a tricky one I'm afraid. The lamp could just be very sensitive to some slight current leakage in the 3 port valve although I wouldn't have expected it, at least not in connection with the DHW OFF signal.
That's a tricky one I'm afraid. The lamp could just be very sensitive to some slight current leakage in the 3 port valve although I wouldn't have expected it, at least not in connection with the DHW OFF signal.
Yes the light on the room stat
Although its not on all the time and it is very dim when it is on!
It does look and sound like a bit of volt leakage
it is an odd one as its not all the time when the hot water is off either! unless its a bad connection somewhere which I will check
all seems to be working though
Although its not on all the time and it is very dim when it is on!
It does look and sound like a bit of volt leakage
it is an odd one as its not all the time when the hot water is off either! unless its a bad connection somewhere which I will check
all seems to be working though
May well have found the issue
I had a stray strand of live wire very very close to terminal 1 on the programmer which is the DHW off! I wonder if this was feeding down to the cylinder stat and mid position valve and then back to the stat as I now can't reproduce the dim LED
I had a stray strand of live wire very very close to terminal 1 on the programmer which is the DHW off! I wonder if this was feeding down to the cylinder stat and mid position valve and then back to the stat as I now can't reproduce the dim LED
You can't use a Honeywell stat with an indicator like that with a 3 port valve, as the indicator will misbehave.
Yes I have come to realise that!
I thought I had a stray wire causing power to be back fed but after googling I have come to realise its something to do with the 3 port valve having a low power in the midway position!
I will probably just have to live with it
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