Wiring help urgently please!!!!
Discussion
Evening All,
I am in the process of trying to replace an old thermostat which was usefully located in the hall - pretty much the place in the house least related to the temperature elsewhere - with a wireless job.
Problem I have is figuring out which wires to attach to which connector on the new receiver.
According to the instructions with the receiver, I should be mounting a neutral and a live wire to the receiver terminals. The wiring coming into the receiver, however, contains brown, black, grey and earth.
Which of these should go to Neutral??? As I understand it, Neutral should be blue (which I don't have) and brown, black & grey are L1, L2 & L3.
The old unit didn't help, as it had no bloody markings at all on it!!!
I am in the process of trying to replace an old thermostat which was usefully located in the hall - pretty much the place in the house least related to the temperature elsewhere - with a wireless job.
Problem I have is figuring out which wires to attach to which connector on the new receiver.
According to the instructions with the receiver, I should be mounting a neutral and a live wire to the receiver terminals. The wiring coming into the receiver, however, contains brown, black, grey and earth.
Which of these should go to Neutral??? As I understand it, Neutral should be blue (which I don't have) and brown, black & grey are L1, L2 & L3.
The old unit didn't help, as it had no bloody markings at all on it!!!
Busamav said:
If I remember correctly , black became blue and brown became red .
I think it was black became blue and red became brown (the second being the other way round to yours), but I've got modern wiring and instructions for a brand new device.I'm starting to wonder if the modern wiring is the right wiring for this application!!
I forgot to say in my first post that only the brown and grey wires were connected to the old thermostat.
I've followed these up to where they connect into the boiler, and they maintain the brown & grey routes all the way up.
The cable going into the boiler does contain a blue wire (along with black, brown, grey and earth), but this isn't connected to anything.
I'm flummoxed! If I just go by trial and error, will I actually risk blowing anything up?
I've followed these up to where they connect into the boiler, and they maintain the brown & grey routes all the way up.
The cable going into the boiler does contain a blue wire (along with black, brown, grey and earth), but this isn't connected to anything.
I'm flummoxed! If I just go by trial and error, will I actually risk blowing anything up?
Smiler. said:
From your description, the wire from the stat is not the same one as the wire to the boiler.
There is probably a wiring centre (box with a long terminal strip & a label on the lid).
This should help with identifying what the wires do.
How old is the system?
You are correct, there is a central box, but I have followed through that in my previous description. There is probably a wiring centre (box with a long terminal strip & a label on the lid).
This should help with identifying what the wires do.
How old is the system?
The boiler is about 18 months old. The whole house was rewired about 5 years ago. I'd guess that the actual thermostat I'm replacing probably dates back to the seventies.
Smiler. said:
Valves not relevant for a combi, do you have a wiring diagram for the boiler?
No, unfortunately not. I was foolishly assuming that with only two wires, it couldn't be that complicated!I'm assuming the old one must also have had one wire to live and one to neutral. Am I running the risk of seriously damaging stuff if I try it and get the 50/50 guess wrong? I presume it will just be changing the direction of flow through the thermostat, rather than changing the voltage levels or anything?
Further update - there's no voltage on either wire, and the receiver needs power to run.
For the moment, therefore, I can have heating either on or off by connecting or disconnecting the wires.
The logical thing would seem to be removing the central thermostat altogether, and just fitting thermostatic valves to the last couple of radiators without them.
Plan B emerges!
For the moment, therefore, I can have heating either on or off by connecting or disconnecting the wires.
The logical thing would seem to be removing the central thermostat altogether, and just fitting thermostatic valves to the last couple of radiators without them.
Plan B emerges!
Kermit power said:
Further update - there's no voltage on either wire, and the receiver needs power to run.
For the moment, therefore, I can have heating either on or off by connecting or disconnecting the wires.
The logical thing would seem to be removing the central thermostat altogether, and just fitting thermostatic valves to the last couple of radiators without them.
Plan B emerges!
From the boiler take a neutral and live to power the receiver, connect to relevant terminals. take the two wires that you join to run the heating, and connect them to the switched terminals on the receiver, and Roberts your mothers brother.For the moment, therefore, I can have heating either on or off by connecting or disconnecting the wires.
The logical thing would seem to be removing the central thermostat altogether, and just fitting thermostatic valves to the last couple of radiators without them.
Plan B emerges!
Do not put 240 onto switched wires.
dirkgently said:
Kermit power said:
Further update - there's no voltage on either wire, and the receiver needs power to run.
For the moment, therefore, I can have heating either on or off by connecting or disconnecting the wires.
The logical thing would seem to be removing the central thermostat altogether, and just fitting thermostatic valves to the last couple of radiators without them.
Plan B emerges!
From the boiler take a neutral and live to power the receiver, connect to relevant terminals. take the two wires that you join to run the heating, and connect them to the switched terminals on the receiver, and Roberts your mothers brother.For the moment, therefore, I can have heating either on or off by connecting or disconnecting the wires.
The logical thing would seem to be removing the central thermostat altogether, and just fitting thermostatic valves to the last couple of radiators without them.
Plan B emerges!
Do not put 240 onto switched wires.
Will the neutral and the phase 2 wires coming out of the boiler in the same cable - which aren't currently connected up - provide the live and neutral you mention, or do these need to come from elsewhere? If so, where?
I think you should get someone in who knows what they are doing as limited knowledge is often more dangerous than none.
It should be a simple thing to work out the wiring, the old thermostat will effectively be an on/off switch (requiring just 2 wires to make a circuit) using a bi-metallic strip to either open or close the circuit.
The new thermostat will have effectively the same circuit control, but will also need a 'live' supply to keep the base box wireless electronics active. Hence the apparently more complicated wiring requirements.
IF you are confident enough to work out which 2 wires are the control circuit into the boiler and then find a 240v supply to the base box it should be simple enough.
But I'm not sure, based on your posts, that you are confident enough to do this. Hence my advice to get a man in for £100 notes to do it for you. I'm honestly not trying to be troll like or condescending but you don't want to be dicking around if you're not sure. It'll end in tears
It should be a simple thing to work out the wiring, the old thermostat will effectively be an on/off switch (requiring just 2 wires to make a circuit) using a bi-metallic strip to either open or close the circuit.
The new thermostat will have effectively the same circuit control, but will also need a 'live' supply to keep the base box wireless electronics active. Hence the apparently more complicated wiring requirements.
IF you are confident enough to work out which 2 wires are the control circuit into the boiler and then find a 240v supply to the base box it should be simple enough.
But I'm not sure, based on your posts, that you are confident enough to do this. Hence my advice to get a man in for £100 notes to do it for you. I'm honestly not trying to be troll like or condescending but you don't want to be dicking around if you're not sure. It'll end in tears
Kermit power said:
The cable currently coming out of the boiler is a new 3-phase cable (as shown in the diagram above) with only phase 1 and phase 3 connecting down to the thermostat. Connecting these two together turns the heating on, and disconnecting them turns it off.
Will the neutral and the phase 2 wires coming out of the boiler in the same cable - which aren't currently connected up - provide the live and neutral you mention, or do these need to come from elsewhere? If so, where?
The reciever should have a set up along the lines of this......Will the neutral and the phase 2 wires coming out of the boiler in the same cable - which aren't currently connected up - provide the live and neutral you mention, or do these need to come from elsewhere? If so, where?
There should be two terminal marked L+N, these are to be wired up with permanent 240v live supply and a neutral. You can take this from the L+N supply for the boiler.
There should also be 3 other terminal, usually marked Common - Sat - Demand or Common - NO - NC or possibly something else.
Basically its a switch, the two wires you describe in your above post need to be connected here. One of them should go to the Common terminal and the other needs to go the terminal that makes contact when the temperature falls, so that will be demand or NO (Normally Open).
Hope this make sense, if not post a picture of the reciever wiring diagram.
Right! Photo time!
Firstly, the new thermostat...
Then the backplate for the thermostat in place, showing the brown and grey wires currently connected together to provide heating, plus the wiring diagram in the instructions.
The wire then feeds up to a junction box thingy. I hasten to add that I am not responsible for the use of the earth wire at this point! The cable on the right comes up from the thermostat.
The earth wire then rejoins the correct colour in another little junction box thing, which I assume is just being used to extend the cable. This attached to the cable coming out of the boiler itself. As you can see, brown and grey synch back up to provide continuity down to the thermostat. You can also see the black, blue and earth wires just poking out of the cable.
Lastly, this is the actual boiler. A Worcester Bosch Greenstar.
Fingers crossed this gives enough info for someone to direct me! I have no worries about extending the wiring from the boiler down to the thermostat, but I'd be less confident if I have to start taking power from elsewhere.
Firstly, the new thermostat...
Then the backplate for the thermostat in place, showing the brown and grey wires currently connected together to provide heating, plus the wiring diagram in the instructions.
The wire then feeds up to a junction box thingy. I hasten to add that I am not responsible for the use of the earth wire at this point! The cable on the right comes up from the thermostat.
The earth wire then rejoins the correct colour in another little junction box thing, which I assume is just being used to extend the cable. This attached to the cable coming out of the boiler itself. As you can see, brown and grey synch back up to provide continuity down to the thermostat. You can also see the black, blue and earth wires just poking out of the cable.
Lastly, this is the actual boiler. A Worcester Bosch Greenstar.
Fingers crossed this gives enough info for someone to direct me! I have no worries about extending the wiring from the boiler down to the thermostat, but I'd be less confident if I have to start taking power from elsewhere.
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