Room thermostat

[ian1888ah]

No multimeter, but were would the fuse be? if taken the back off the stat, and the the pcb and the solders look fine.

 

[ELZ4742]

hmmm im wondering wheather you have got a 24v version and if your boiler is kickin out 240v you may have knackered it.

 

[Spark123]

Can you get hold of a multimeter, borrow one, run down to B&Q etc?

 

[ian1888ah]

it is a 24/240v stat

 

[ELZ4742]

i know im gonna get flamed on this but what i would do if my batteries run out on my tester at midnight
switch off of spur,put the stat wires in connectors link out the yellow and red, and see if the heating comes on. if so those are your live and switch live.
if the stat isnt working when u have put it back together i would suspect a bugered stat
but you shouldnt really do what ive told you.

 

[ian1888ah]

cant get hold of meter, all the shops are closed now. Well with the red to live the yellow to call for heat it should work but doesnt. The water still heats and the boiler fired when you ask for water, just not heat. Cant see the wires in the back of the boiler either.

 

[ian1888ah]

ELZ4742, The red in a chop block, and try the yellow with it to see if the boiler fires?

 

[ELZ4742]

yeah but put the blue in a seperate one as this could be connected to a neutral back at the boiler.

 

[ian1888ah]

connect the blue to were?

 

[ELZ4742]

on its own in a connector block

 

[ian1888ah]

Oh just to make it safe?
I'l try that thanks.

 

[ian1888ah]

ok tried yellow and red 2gether but nothing.

 

[Spark123]

Can you borrow a multimeter off a neighbour, friend, relative?

 

[ian1888ah]

Not really, will have to get one tomorrow then. What am i looking for then, live obvioulsy, but how do i check the others?

 

[Spark123]

First prove there is a supply to the thermostat then take it from there.
Firstly set your meter to a range exceeding 250vAC, black probe on earth, red probe on red. How many volts?