DIY Doctor UK DIY Forums

hi Guys ,
had an attempt installing it to no avail apart from 2 blown fuses put it back to normal all ok.
after reading the installation manual thought this will be easy as it shows in the wiring diagrams in the manual change one wire from the timer then fit the stat wires. I think I made the assumption that the wiring on my
room stat is marked ABC my diagram 123 1=A and so on. can any one point me in the right direction . Cheers PLUMBBOB

OK I wil start again with more info It is a relatively new system (12/08) never had a room stat fitted I wish to install honeywell digital room thermo stat model ( T6620B)-(DT200)I know where the wires go on the boiler/timer -Drayton Lifestyle single channelLP111 as per the wiring diagram this has been on and working from initial installation. It is the wiring of the roomstat itself I cannot get to grips with.

You're not going to get much response without giving a hint about what type of controller you are trying to wire up.

One guess is the old stat had a neutral that the new on doesn't need, but how can I tell???????

[quote="Hughie58"]hi Guys ,
had an attempt installing it to no avail apart from 2 blown fuses put it back to normal all ok.
after reading the installation manual thought this will be easy as it shows in the wiring diagrams in the manual change one wire from the timer then fit the stat wires. I think I made the assumption that the wiring on my
room stat is marked ABC my diagram 123 1=A and so on. can any one point me in the right direction .[/quote]
CHEERS PLUMBBOB
hi guys , this is a new installation dec/08 never had a room stat (No T6620B1008 D200 ) hence the reason for the lack of info .
the timer connected to the boiler is a Drayton lifestyle single channel (LP111).

hi Guys ,
had an attempt installing it to no avail apart from 2 blown fuses put it back to normal all ok.
after reading the installation manual thought this will be easy as it shows in the wiring diagrams in the manual change one wire from the timer then fit the stat wires. I think I made the assumption that the wiring on my
room stat is marked ABC my diagram 123 1=A and so on. can any one point me in the right direction . Cheers PLUMBBOB

OK I wil start again with more info It is a relatively new system (12/08) never had a room stat fitted I wish to install honeywell digital room thermo stat model ( T6620B)-(DT200)I know where the wires go on the boiler/timer -Drayton Lifestyle single channelLP111 as per the wiring diagram this has been on and working from initial installation. It is the wiring of the roomstat itself I cannot get to grips with.

Sorry, but I don't understand what you mean by "change one wire from the timer then fit the stat wires". Or "my diagram 123 1=A and so on".

The new stat needs only two wires connecting. One brings the power to the stat, the other takes it back to the boiler.

You only need to use pins "A" and "B". Nothing else.

Normally, if fitting a timer or stat to a combi boiler, this just requires a link to be removed in the boiler circuitry, and the stat/timer linked in it's place.

Hi Plumbbob,
on my installation manual it shows the room stat with 3 wires
that side of things i understand the diagram shows wires 1,2,3 from their stat diagram ........... honeywell however on the stat it shows A,B,C .so i dont know where 1,2,3 go in relation to A,B,C.

check out the diagram on page 34 in the link below

Google "vokera.co.uk/productdetails.asp?prodid={5FAE77B0-61B2-4A89-9114-1E48630FA8D3}&id={7F682E9E-0C3C-4153-BBE7-45B06195D769}&catid={76F0C0AB-3C75-4D4E-A894-D07BAA97D66C}&n=compactse"

many thanks for your patience Hughie

Ah, now I see what you mean!

Looking at the diagram of the Vokera, (diagram 29a?) I can see what the problem is.

That diagram is for the old type of mechanical thermostat not the new electronic stats that are wired differently.

To help changeover speed, old thermostats needed a ballast resistor connected to the neutral (shown as the oblong connected to pin 3. Your new thermostat does not need the neutral at all (using it makes fuses go bang, but you already know that!) so just ignore it.

So for wiring, connect pin "1" to "A" and "2" to "B" and lose wire "3".

Easy!

Thanks Plumbbob ,
that sound a lot easier to understand ,cant try it yet away for 5 days in the morning where hopefully I will not need a thermostat.
adios amigo Hughie