breezer said:
Are these what you want?
Thermostat dies, new one blows the fuse. HELP!
- Thread starter Thermostathelp
- Start date
Are these what you want?
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Also, I have just removed the new thermostat, leaving the wires bare, and replaced the blown fuse. The control panel has powered back up again, so it would certainly point to how the new thermostat was wired.
your wiring center (the first pic of the last post) is a bit of a mess - they're normally 12 way chocolate blocks.
Still, this may not matter. It's looking very likely that the earch conductor was used for something that's not an earth, which is naughty (and a bit unsafe, and against the wiring regs). but, onward in order to get your heating working.
In the wiring center, there are a lot of flexes coming in and it's hard to identify what is what. There is a chocolate block which has a lot of earth conductors in it, which is most likely actually an earth.
If we assume that the earth core in the thermostat flex is used for something else, then it follows that at least one (and hopefully only one) of the flexes in the wiring center has it's earth core connected somewhere else. Find that, and tell us what it connects to. This will help us work out what wire is what.
Was it the brown wire which you tested and found 230v on?
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Other things to note, while you're having a look:-
- if the earth has been misused then you should consider rewiring that cable with a 3 core + earth instead. Failing that, at the very least put a note in the wiring center and inside the thermostat saying something along the lines of "beware: some spanner has used the earth core as a live conductor".
- the new stat is not as good as the old stat. your old stat has an anticipator, which is a small resistor used as a heater, which has the effect of reducing the amount of boiler cycling and improving the temperature control abilities of the stat. I'd strongly recommend reusing the danfoss one.
Still, this may not matter. It's looking very likely that the earch conductor was used for something that's not an earth, which is naughty (and a bit unsafe, and against the wiring regs). but, onward in order to get your heating working.
In the wiring center, there are a lot of flexes coming in and it's hard to identify what is what. There is a chocolate block which has a lot of earth conductors in it, which is most likely actually an earth.
If we assume that the earth core in the thermostat flex is used for something else, then it follows that at least one (and hopefully only one) of the flexes in the wiring center has it's earth core connected somewhere else. Find that, and tell us what it connects to. This will help us work out what wire is what.
Was it the brown wire which you tested and found 230v on?
----------------------------------------------------------------------
Other things to note, while you're having a look:-
- if the earth has been misused then you should consider rewiring that cable with a 3 core + earth instead. Failing that, at the very least put a note in the wiring center and inside the thermostat saying something along the lines of "beware: some spanner has used the earth core as a live conductor".
- the new stat is not as good as the old stat. your old stat has an anticipator, which is a small resistor used as a heater, which has the effect of reducing the amount of boiler cycling and improving the temperature control abilities of the stat. I'd strongly recommend reusing the danfoss one.
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There are 8 blocks, which contain the following wires:
1. 5xBlue
2. 1xRed, 1xBrown
3. 2xGreen/Yellow, 1xGrey
4. 4xGreen/Yellow
5. 1xGreen/Yellow, 1xWhite
6. 1xBlue, 2xBrown, 1xRed
7. 1xYellow, 1xBrown
8. 1xBlack, 1xBrown
I'm happy to use the Danfoss thermostat if it works, can't think of what else could have cause the original fault though.
1. 5xBlue
2. 1xRed, 1xBrown
3. 2xGreen/Yellow, 1xGrey
4. 4xGreen/Yellow
5. 1xGreen/Yellow, 1xWhite
6. 1xBlue, 2xBrown, 1xRed
7. 1xYellow, 1xBrown
8. 1xBlack, 1xBrown
I'm happy to use the Danfoss thermostat if it works, can't think of what else could have cause the original fault though.
ollski said:
Don't know what wire's what at the moment, so bridging something won't prove much at this stage.
Thermostathelp said:
And yes, it was the brown wire which measured 230v.
ollski said:
I can't remember how the old stat was wired originally.
B
breezer
sorry for th delay i have been out.
yes those are the pics i wanted to see, and your description of what goes where is marvelous.
if you connect your stat between brown and green / yellow it will work fine.
you should how ever change the cable to a 3 core and earth as your new stat requires an earth
OR if you can find out which cable it is you can remove the blue and swop that for the green / yellow then you can use the green yellow for earth
you should also sleave the blue with brown tape at both ends to signify it is live
yes those are the pics i wanted to see, and your description of what goes where is marvelous.
if you connect your stat between brown and green / yellow it will work fine.
you should how ever change the cable to a 3 core and earth as your new stat requires an earth
OR if you can find out which cable it is you can remove the blue and swop that for the green / yellow then you can use the green yellow for earth
you should also sleave the blue with brown tape at both ends to signify it is live
Thermostathelp said:
Sounds like you have a 3 port mid position valve. That valve has a flex which contains brown, grey, orange,blue. Find that cable.
The brown from that cable is connected to one of the room stat wires, and nothing else. It's either 2, or 8, from you chart above. Whichever wire that is, remember it, and lets call it "CH DEMAND".
Fit the danfoss stat. Connect the brown - we know this is live - to the center terminal (pin 1, i think). Connect "CH DEMAND" to the far right terminal (pin 2, i think). Connect the remaining wire to the leftmost terminal (pin 4 (neutral) i think).
That should sort it out.
B
breezer
i would not do that if i were you (as mentioned above) the reason being i will bet that the blue is a neutral, old stats had a small resistor in them to make the stat more acurate, so the resistor goes across live and neutral, the 3rd wire (green / yellow) being the switch wire
your list mentions all blues together so it looks like it is a neutral, connecting it in the stat will mean it will go bang when it cools.
your new stat only requires 2 connections (live and switched live) and earth
your list mentions all blues together so it looks like it is a neutral, connecting it in the stat will mean it will go bang when it cools.
your new stat only requires 2 connections (live and switched live) and earth
Thanks slippyr4 and breezer.
Managed to get it going now, the danfoss one is knackered though.
I will not freeze to death tonight.
Thanks lads.
Managed to get it going now, the danfoss one is knackered though.
I will not freeze to death tonight.
Thanks lads.
good effort. but as breezer and I said, change that cable. Using an earth for a live is a silly game.
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