UPDATE!! Wires for thermostat
- Thread starter emailrob
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What is neutral wire? Rob.
Anything that uses two wires means one wire must live.
A wire going to a switch will be 'live'
A wire leaving the switch is a 'switched live'
A wire going to a 'load' (lamp/motor/element etc) will usually be a switched 'live'
A wire leaving a 'load' is a neutral.
Usually lives are 'red'. Switched lives can be 'red' or 'black with a red flag'
Neutrals are 'black'.
On boilers you will find 'lives' are 'brown' and 'neutrals' 'blue'.
On mid position valves you get blue/grey/white/orange and another
I think you should use a red or brown for your 'live' to the stat ( which is a switch) and a black(with red flag) for the return.
Of course you can use any colour you want, but you need to identify which wire is which at each end, as you know greens and green/yellow are for earth wires so avoid them
Anything that uses two wires means one wire must live.
A wire going to a switch will be 'live'
A wire leaving the switch is a 'switched live'
A wire going to a 'load' (lamp/motor/element etc) will usually be a switched 'live'
A wire leaving a 'load' is a neutral.
Usually lives are 'red'. Switched lives can be 'red' or 'black with a red flag'
Neutrals are 'black'.
On boilers you will find 'lives' are 'brown' and 'neutrals' 'blue'.
On mid position valves you get blue/grey/white/orange and another
I think you should use a red or brown for your 'live' to the stat ( which is a switch) and a black(with red flag) for the return.
Of course you can use any colour you want, but you need to identify which wire is which at each end, as you know greens and green/yellow are for earth wires so avoid them
Sorry, should have provided more info.
The wires are two seperate wires, like a speaker cable, that type of wire is needed.
I'll give the company a call and see what they think, as the instructions are not clear enough for my liking!!
thanks for the reply.
rob
The wires are two seperate wires, like a speaker cable, that type of wire is needed.
I'll give the company a call and see what they think, as the instructions are not clear enough for my liking!!
thanks for the reply.
rob
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emailrob,
Is this a special thermostat that just has a low voltage wire connecting it to the boiler?
Normal thermostats are mains-voltage, most definitely not wired in bell-wire (or anything similar), and usually have three wires (a live, switch live, neutral (plus of course and earth).
If it's a special low-voltage one designed to go on the boiler then cool, but the description has made me think you should be careful here - I have a Horstmann programable stat which can be fitted to any boiler, and it's the same wiing as a normal mains thermostat.
Hope this helps, please provide more info if you need more advice..
Paul
Is this a special thermostat that just has a low voltage wire connecting it to the boiler?
Normal thermostats are mains-voltage, most definitely not wired in bell-wire (or anything similar), and usually have three wires (a live, switch live, neutral (plus of course and earth).
If it's a special low-voltage one designed to go on the boiler then cool, but the description has made me think you should be careful here - I have a Horstmann programable stat which can be fitted to any boiler, and it's the same wiing as a normal mains thermostat.
Hope this helps, please provide more info if you need more advice..
Paul
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Hi
Sorry for the delay, been away on business
It has three holes for wires but I believe only two of them are used. It is run by a battery and does not have any mains connection.
If it helps, it's this one:
https://www.screwfix.com/app/sfd/cat/pro.jsp?ts=03528&id=17585
Hope this info helps!!!
Rob
Sorry for the delay, been away on business
It has three holes for wires but I believe only two of them are used. It is run by a battery and does not have any mains connection.
If it helps, it's this one:
https://www.screwfix.com/app/sfd/cat/pro.jsp?ts=03528&id=17585
Hope this info helps!!!
Rob
B
breezer
we have one similar, it too has a battery, but it SWITCHES mains, so 1mm or 1.5mm twin and earth must be used.
the 3 connections are common NO (normally open and NC normally closed, most boilers use common and normally open, you should put the earth wire in green/yellow sleaving and a choc bloc
the 3 connections are common NO (normally open and NC normally closed, most boilers use common and normally open, you should put the earth wire in green/yellow sleaving and a choc bloc
OK. Got my wire and was ready to go. However got a bit stuck
I've uploaded a picture of the wiring block so that you can see what I'm talking about. http://f1.pg.photos.yahoo.com/ph/emailrob/vwp?.dir=/Boiler&.dnm=Boiler+wiring.jpg&.view=t
The manual says I must wire it into the 'external timer' section, and retain the blue wire that goes between 3 and 4 blocks.
The wiring between 10 9 and 8 goes to the mains. If I disconnect this, and replace the wires with the one from the new programmable thermostat, it the heating does not come on. I've got the timer as 'on' and the switch on the boiler onto 'timed'.
Do I need to wire in the timer into holes 10 9 and 8 AS WELL as the external power, or instead?
Hopefully this helps someone to help me!!!
cheers
rob
I've uploaded a picture of the wiring block so that you can see what I'm talking about. http://f1.pg.photos.yahoo.com/ph/emailrob/vwp?.dir=/Boiler&.dnm=Boiler+wiring.jpg&.view=t
The manual says I must wire it into the 'external timer' section, and retain the blue wire that goes between 3 and 4 blocks.
The wiring between 10 9 and 8 goes to the mains. If I disconnect this, and replace the wires with the one from the new programmable thermostat, it the heating does not come on. I've got the timer as 'on' and the switch on the boiler onto 'timed'.
Do I need to wire in the timer into holes 10 9 and 8 AS WELL as the external power, or instead?
Hopefully this helps someone to help me!!!
cheers
rob
B
breezer
from what i see 10 9 & 8 should be left as the picture shows.
by any chance does terminal 4 say L? (i cant see behind the blue wire)
I should say your room stat goes across
3 + 4 (C & NO at your stat) you should also remove the blue wire when you do this
I say all the above because i assume that as it is your boiler works?
your room stat (when wired in) will break the link from 3 to 4 when the room is hot enough
by any chance does terminal 4 say L? (i cant see behind the blue wire)
I should say your room stat goes across
3 + 4 (C & NO at your stat) you should also remove the blue wire when you do this
I say all the above because i assume that as it is your boiler works?
your room stat (when wired in) will break the link from 3 to 4 when the room is hot enough
thanks for the reply.
Yes terminal 4 is Live. I'll swap the blue wire for the thermo and see what happens tomorrow. Shall I wire the earth into 6?? what about the earth at the other end of the wire, can I just tape this off?
cheers
Yes terminal 4 is Live. I'll swap the blue wire for the thermo and see what happens tomorrow. Shall I wire the earth into 6?? what about the earth at the other end of the wire, can I just tape this off?
cheers
B
breezer
i can not see what 6 says it is, but if it is earth then yes, or you could put it on the terminal above the one with the other earth wires, and yes about the other end, but it should be green / yellow tape or sleaving
Out of interest I'm trying to make sense of your 10 term.block.
I note terminals 1 & 2 LIVE and NEUTRAL have no wires on the top side.
I assume they have been removed for the photo.
Alternatively does the external timer have a separate feed from the mains supply.
I can follow breezer's reasoning to remove the link between terms. 3 & 4 and replace with the room stat. Although to break the link I would have thought the stat switch would be 'normally closed' and would open to break the link and not 'normally open'. No doubt he will clarify.
To wire it in the external timer section The earth would go to term. 10 or 6 which are linked.
To me nothing would go to Neutral terminals 9 or 5 or 2 which are also linked, because there is no neutral. the wire goes to the room stat which is a switch as a 'live' and leaves as a 'switched live'.
This leaves the 'live' passing through term.8. If the wire to/from external timer was removed from the top it could be connected (choc block)to your stat and the second wire from your stat would go into term. 8.
That's how I see it! and maybe other terminal blocks don't have a link across term. 3 and 4.
I note terminals 1 & 2 LIVE and NEUTRAL have no wires on the top side.
I assume they have been removed for the photo.
Alternatively does the external timer have a separate feed from the mains supply.
I can follow breezer's reasoning to remove the link between terms. 3 & 4 and replace with the room stat. Although to break the link I would have thought the stat switch would be 'normally closed' and would open to break the link and not 'normally open'. No doubt he will clarify.
To wire it in the external timer section The earth would go to term. 10 or 6 which are linked.
To me nothing would go to Neutral terminals 9 or 5 or 2 which are also linked, because there is no neutral. the wire goes to the room stat which is a switch as a 'live' and leaves as a 'switched live'.
This leaves the 'live' passing through term.8. If the wire to/from external timer was removed from the top it could be connected (choc block)to your stat and the second wire from your stat would go into term. 8.
That's how I see it! and maybe other terminal blocks don't have a link across term. 3 and 4.
B
breezer
Mandate i see what you are thinking but i should assume that terminals 1 & 2 are for a permanent feed if the boiler has its own onboard timer )could be wrong)
I also see what you are thinking regarding my thoughts on the room stat and the link, but put it this way, if the room is warm stat goes off no heating required and so on, but the boiler does not know what the room temp is so it needs a link to say it is cold (so heating comes on) all the time otherwise the boiler may never come on. it then it sees its own water temp stat and turns the boiler off
here is a thought. if the stat is wired into terminal 8 as you suggest what happens when a h/w tap is turned on? cold water because the room stat is saying its warm and no boiler required
But wired as it is the timer says either h/w or ch should be on so the boiler comes on and heats the h/w if the room stat says its cold the the pump comes on and does its thing.
But it is only a thought
I also see what you are thinking regarding my thoughts on the room stat and the link, but put it this way, if the room is warm stat goes off no heating required and so on, but the boiler does not know what the room temp is so it needs a link to say it is cold (so heating comes on) all the time otherwise the boiler may never come on. it then it sees its own water temp stat and turns the boiler off
here is a thought. if the stat is wired into terminal 8 as you suggest what happens when a h/w tap is turned on? cold water because the room stat is saying its warm and no boiler required
But wired as it is the timer says either h/w or ch should be on so the boiler comes on and heats the h/w if the room stat says its cold the the pump comes on and does its thing.
But it is only a thought
well slowly getting nowhere!!
I have to leave terminals 10 9 8 wired, otherwise the boiler has no mains power and is dead.
If I remove the wire between 3 and 4 and do nothing else, the boiler does not function (power but not heating etc).
If I put the live from the thermo in 4 and neutral in 5 (tried 3 also) it does not come on. The thermo is on and in the mode where the boiler should be on, but it's not.
Incidentally, when wired into 4 and 5. I can turn the boiler onto constant and it comes on, which does not happen if the blue wire is missing.
I enclose a picture from the manual, probably should have done this earlier....
Anyway, elsewhere in the manual it says if an external programmable thermo is to be fitted, the connections should go in place of 10 9 and 8, but then the boiler has no power?
Hope some of this makes sense to you guys!!
http://f1.pg.photos.yahoo.com/ph/emailrob/vwp?.dir=/Boiler&.dnm=instructions.jpg&.view=t
I have to leave terminals 10 9 8 wired, otherwise the boiler has no mains power and is dead.
If I remove the wire between 3 and 4 and do nothing else, the boiler does not function (power but not heating etc).
If I put the live from the thermo in 4 and neutral in 5 (tried 3 also) it does not come on. The thermo is on and in the mode where the boiler should be on, but it's not.
Incidentally, when wired into 4 and 5. I can turn the boiler onto constant and it comes on, which does not happen if the blue wire is missing.
I enclose a picture from the manual, probably should have done this earlier....
Anyway, elsewhere in the manual it says if an external programmable thermo is to be fitted, the connections should go in place of 10 9 and 8, but then the boiler has no power?
Hope some of this makes sense to you guys!!
http://f1.pg.photos.yahoo.com/ph/emailrob/vwp?.dir=/Boiler&.dnm=instructions.jpg&.view=t
B
breezer
Where is your incoming mains connected to? acording to the drawing it should be on 1+2 but there is nothing there (it was mentioned earlier, but not by me, and it said had you removed it to take the picture)
you should have your incoming mains on 1+2 your stat where i said and your timer wired as it is (almost) the timer should be fed from your boiler not directly from the mains
the live to the boiler should be on 8 the neutral to the timer should be on 9 and the switch wire from the timer on 7
as i can only go by what i see (dont do boilers for a living) i didn't ask where the mains incoming is as i assumed it came from the timer as a switched live (my old boiler where i used to live did just that)
you should have your incoming mains on 1+2 your stat where i said and your timer wired as it is (almost) the timer should be fed from your boiler not directly from the mains
the live to the boiler should be on 8 the neutral to the timer should be on 9 and the switch wire from the timer on 7
as i can only go by what i see (dont do boilers for a living) i didn't ask where the mains incoming is as i assumed it came from the timer as a switched live (my old boiler where i used to live did just that)
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