Thermostat wiring driving me mad! Help please

[smelllikewee2010]

Hi

The thermostat to my CH was cut off and the wire locations not noted. I have a new sunvic TLX 9201 thermostat which i have been trying to wire in for ages.

I have blown the fuse a couple of times and at most have managed to get the heating to come on for up to an hour at which point it switches off and refuses to come back on for at least 12hrs.

I have four wires Red, Blue, Yellow and bare copper, mt stat is a four wire one, details here:

http://www.sunvic.co.uk/datasheet_tlx9000.html

Any help of wire locations would be most helpful, getting cold now. What might cause it to switch off and not on again?

Many thanks

Nice forum.

Nath

 

[D_Hailsham]

I have four wires Red, Blue, Yellow and bare copper, mt stat is a four wire one,

Do you have a multimeter?
If so check the voltage between Red and Blue wires when the CH timer is turned on. Do the same between Red/Yellow and Blue/Yellow.
If Red/Blue and Red/Yellow reads 240V wiring is as follows:

Red to terminal 1
Yellow to terminal 3
Blue to terminal 4

Terminal 2 is not used (it's for cooling systems).
The bare wire is not used.
is your live from the timer and connects to terminal

 

[smelllikewee2010]

I have four wires Red, Blue, Yellow and bare copper, mt stat is a four wire one,

Do you have a multimeter?
If so check the voltage between Red and Blue wires when the CH timer is turned on. Do the same between Red/Yellow and Blue/Yellow.
If Red/Blue and Red/Yellow reads 240V wiring is as follows:

Red to terminal 1
Yellow to terminal 3
Blue to terminal 4

Terminal 2 is not used (it's for cooling systems).
The bare wire is not used.
is your live from the timer and connects to terminal

ok I have tried that wire order,the ch box lights up but no pump
or heating still! I don't have a multimeter so I can't try that
any other ideas?

Thanks for your help

nath

 

[marcr]

Blue to terminal 4 (neutral)
Bare core to earth terminal on backplate or unused. Should be sleeved.

Try Red to terminal 1 and Yellow to terminal 3 (normal) or
Red to terminal 3 and Yellow to terminal 1

These should be the only two options.
Which setup made it work before?

Otherwise suspect zone valve motor faulty/ on it's way out and not giving switch live to pump/boiler (if zone valves used)
Can you see this valve or the lever moving across when heating on?

 

[smelllikewee2010]

Update, had a theory about the heating switching off. We have a back boiler which heats our water and warms our radiators. I wondered if the hearing was switching of because the tank was too hot. I tried to switch it on, no joy, then I ran some hot water and went back, it switched on fine.

What is going on here? Is it purely the thermostat not doing it's job?

Thanks again

nath

 

[marcr]

Strongly suspect 3-port mid position zone valve stuck in hot water only position or central heating 2-port zone valve stuck in closed position.

Can you see this valve? In the airing cupboard maybe? Black cable going to it. It should have a manual open position that you can move the lever over to.
Run off some more hot water to drop the temperature and fire the boiler and you should get some heat to the radiators While it's going.

 

[wetshoes]

Buy a multimeter or get someone in !

 

[smelllikewee2010]

Hi,

Thanks for all the replies.

I have tried the other wiring options but no joy, been away so no multimeter.

When i run some hot water out it does fire up again for about 15min then off again.

If it helps the thermostat only clicks on off at 12degress and makes no difference to the boiler whether it clicks on off or not!

Any other tips? Otherwise getting someone out very soon! -4 tonight!

thanks

nath

 

[AL66]

I would (and have done in the past) make a diagram of all the wiring in the system from the incoming mains connection, programmer, thermostats (room and tank), motorised valves, boiler, pump and any wiring junction boxes, etc. Then study it until you understand what's going on, then the required connections should be obvious - you might even then realise it was wired up wrong in the first place!

Good luck.