Ok ........i wanted to replace my room thermostat with a digital one but when i undone the old one and compared it to the new one the wiring was different, old one had red into 1 yellow into 3 and blue into 4 .....new one had numbers 1 2 3 and said nothing about the coloured wires ......after looking up on the net i connected up turned on the electric something went pop in the cupboardwhere the hot water cylinder and controls are and now i have no heating ....hot water still works tho please if anyone has a clue what has happened please get in touch (see profile) thanks guys !!!!!
What have i done?????? help
- Thread starter loonyangel
- Start date
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be useful info to know which model roomstat you tried to install
took out sunvic tlx2259 and tried to put in a sunvic tlx7501
this stat u fitted is volt free does not need neutral
remove the neutral, fit red in 1, yellow in 2 (may be 3) replace fuse in spur and hope u have not damaged your new stat
remove the neutral, fit red in 1, yellow in 2 (may be 3) replace fuse in spur and hope u have not damaged your new stat
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did try it that way round before i tried connecting the neutral , the heating came on but the stat did'nt turn off the heating when turned down , i have put the old stat back on but still no heating it won't fire up at all ,as i said something 'popped' in the cupboard when i turned the electric back on can't find any fuses tho and all other electrics fine in the house ??????
Any thanks guys please keep the ideas coming !!!!
Your fused spur may be under the boiler. What you are looking for is like a single light switch with a fuse holder to the left of it.
Most often it is in the airing cupboard. Also check that a mcb hasn't popped out on the main consumer unit.
I do not know this Sunvic so assuming CG is correct ignore the blue and make safe, red will be live in and yellow live out to zone valve, boiler pump etc.
I would go with red =1, yellow =3.
Often 2 is the make on fall terminal eg for cooling.
Most often it is in the airing cupboard. Also check that a mcb hasn't popped out on the main consumer unit.
I do not know this Sunvic so assuming CG is correct ignore the blue and make safe, red will be live in and yellow live out to zone valve, boiler pump etc.
I would go with red =1, yellow =3.
Often 2 is the make on fall terminal eg for cooling.
Here's a wiring diagram for what you have http://www.sunvic.co.uk/rjtypicalprog.pdf
As Dave say's, sounds like you have popped a fuse by connecting phase and neutral. Remove the blue wire between 2 and four and make safe.
As Dave say's, sounds like you have popped a fuse by connecting phase and neutral. Remove the blue wire between 2 and four and make safe.
i just checked switch under the boiler thats fine , its firing up when i turn on the hot water control in the airing cupboard but not firing up when i turn on the heating
no fuse's in the airing cupboard it's self tho so i really dunno what went pop in there it did sound like a fuse blowing but there ain't any !! lol
as soon as i can get the heating going ( i have fitted the old stat back on now) i will try the wiring that way
no fuse's in the airing cupboard it's self tho so i really dunno what went pop in there it did sound like a fuse blowing but there ain't any !! lol
as soon as i can get the heating going ( i have fitted the old stat back on now) i will try the wiring that way
mmmm yeah thats what i was thinking 
when i put the heating on its not moving over
when i put the heating on its not moving over
I got a call from a friend who had done exactly the same thing last month.
The short circuit had blown a track on his programmer circuit board. The thin metal strip had acted like a fuse and melted. It was easily seen and a quick dab with a blob of solder & soldering iron soon sorted it.
You could check with a multimeter that you are getting a live at the central heating "on" terminal at the programmer (there should be a diagram inside it to help you identify which terminal this is, or try the other end of the cable at the thermostat, probably the red wire as gas4you pointed out) if there's no live with the CH set to "on" likely you have blown the programmer relay or circuit board.
Assuming you have a traditional system (not a combi) to confirm this and as a temporary measure, you could connect the CH "on" wire leaving the programmer to the HW "on" terminal and the system should work. It would just mean that the CH & HW will both be controlled by the HW timings.
The short circuit had blown a track on his programmer circuit board. The thin metal strip had acted like a fuse and melted. It was easily seen and a quick dab with a blob of solder & soldering iron soon sorted it.
You could check with a multimeter that you are getting a live at the central heating "on" terminal at the programmer (there should be a diagram inside it to help you identify which terminal this is, or try the other end of the cable at the thermostat, probably the red wire as gas4you pointed out) if there's no live with the CH set to "on" likely you have blown the programmer relay or circuit board.
Assuming you have a traditional system (not a combi) to confirm this and as a temporary measure, you could connect the CH "on" wire leaving the programmer to the HW "on" terminal and the system should work. It would just mean that the CH & HW will both be controlled by the HW timings.
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