Room thermostat

[ian1888ah]

I replaced the thermostat, but connected the wire up wrongly. There was a pop and the trip switches went.
Iv wired it up correctly now but it doesnt heat the radiators when you turn it up. The boiler has fired but it seems the thermostat doesnt call for heat?

Any ideas anyone?

 

[Spark123]

Combi boiler? Which trip went? There will probably be a fuse in a fused connection unit near the boiler, have you checked this? Is it working for hot water? Failing this, you have either still not got the thermostat wired properly or you may have popped the PCB or a fuse on it. Maybe worth also consulting a heating engineer.

 

[ian1888ah]

Yes it is a combi boiler.
i have 3 wires, yellow, red and blue and 3 connections.
dem 1
com 2
sat 3
The kitchen appliances and downstairs sockets tripped?

 

[Spark123]

What do the 3 connections refer to, COM I take as common, DEM poss. demand, SAT = ???. Earth wire? These in the boiler or the stat?
http://wiki.diynot.com/electrics:how_to_replace_a_room_stat

 

[ian1888ah]

common, demand and satisfied.
earth was wired on the old one, but not needed on the new one.
these are on the stat not boiler.

thanks

 

[Spark123]

How were the wires connected to the old stat and how were they labelled? Some stats require a neutral connection, possibly the older one had a neutral? The satisfied may not be required, shown as the N/C in Robs guide:
http://wiki.diynot.com/electrics:how_to_replace_a_room_stat

 

[ian1888ah]

not sure how they were connected in the old 1 im afraid. dont the colours on the wires indicate were they go?

 

[breezer]

not sure how they were connected in the old 1 im afraid. dont the colours on the wires indicate were they go?

no.

 

[ELZ4742]

thats odd that you would have that on a room stat, only ever seen that on a tank stat.
anyhoo, i would suspect the previous stat would have been red - common
yellow - demand and blue neutral. by the sounds of things you wont need the blue so this can be disconnected.

check out whats in the boiler with regards to the above, check that the send and return (other 2 connections that are not L N E ) are yellow and red.

 

[bernardgreen]

Sounds like programmable thermostat. Has a changever relay contact on three terminals. Battery operated and needs no neutral

 

[ELZ4742]

inded, it be useful to know what make and model your using.

 

[securespark]

common, demand and satisfied.

Describes my trip to massage parlour the other day....!

 

[ian1888ah]

The make is a sunvic tlx4101, its only a very basic one. I have tried red to common and and the blue and yellow on both but it still doesnt seem to call for heat?

 

[RF Lighting]

Brown = red
Black = yellow
Grey = blue

It is a slightly different model but should give you an idea.

 

[Spark123]

My incling would be that the blue is neutral from what I can gather the tlx4101 is a 2 wire thermostat hence a neutral is not required. If you have a look at the boiler you should be able to see the other end of the 3c+e cable. Does blue connect to N? If so the switching will be between red and yellow, terminate the blue in a piece of chock block at the thermostat.
I still think you have probably also popped a fuse or the PCB, do you have a multimeter?