Valiant Turbomax and honeywell T40

[tomlewis007]

I have a wiring problem, im an electronic engineer but the manual isnt very clear at all.

I have three connections on the valliant 3 4 and 5

it says in the book that if 4 and 5 are closed then the boiler will be on.

I shorted the two and i get nothing.

I am looking to upgrade the thermostat to one i that is programable i like the heatmiser ones any views?

Many thanks

-Tom

 

[corgiman]

oh dear you may have killed your PCB

 

[tomlewis007]

the hot water is working fine just?

There are 21v connections could i not use another thermostat?


thanks

-Tom

 

[corgiman]

sorry i thought you meant the boiler wasnt working

as long as you dont whack 240 down them you can use what ever stat you like

I think honeywell the one and the three are the switch, and it dont matter what voltage you use

beware some of them are 240 (drayton etc)

 

[chrishutt]

Normally on Vaillants terminals 3, 4 and 5 on the boiler are for connecting a mains voltage stat, 3 being live out, 4 being switched live back and 5 being neutral for the stat accelerator. Vaillant say do not use the low voltage connections.

You say you connected 4 and 5 and got nothing, but you should have connected 3 and 4! This switches on the heating if other control panel switches (and any other controls wired in - timer for example) are calling for heat.

 

[tomlewis007]

Great thanks i will try this tomorrow.

Mnay many thanks

Its freezing tonight im all tucked up in bed