I am reasonable at DIY however having a problem in wiring up a new room thermostat to my new boiler.

The boiler (Ravenheat Little Star) only has two connections for room stat and the stat (Drayton Digistat 3) has 3 connections.
Can anyone help with what connects to what.

I've rewired the house with no problems but this has me a bit bewildered.

Any help would be gratefully received

Mark

williamsmark wrote in
:

I am reasonable at DIY however having a problem in wiring up a new room
thermostat to my new boiler.

The boiler (Ravenheat Little Star) only has two connections for room
stat and the stat (Drayton Digistat 3) has 3 connections.
Can anyone help with what connects to what.

I've rewired the house with no problems but this has me a bit
bewildered.

It has

(1) a common connection
(2) Call for heat
(3) heating satisfied

(I would have called 2 normally open, and 3 normally closed, but WTH?)

So I guess I'd use 1 and 3.

I did, and mine works.

You might want to check that your boiler requires a volts free closure at
the thermostat, it's a million it will.

mike

mike

Think I'm correct in saying that a 3 wire system is Live, Neutral and Heat.
My old thermostat needed a Live/Neutral supply to drive it but only needed
the live to be switched to the Heat to control the boiler. Have now fitted a
new 2 contact room stat and have only used the Live and Heat wires and
isolated the Neutral as this was no longer needed... all works fine.

In order to use you're existing stat I presume you will need a Neutral feed
to the stat or you could simply buy a new 2 wire stat.

Andy



"williamsmark" wrote in message
...

I am reasonable at DIY however having a problem in wiring up a new room
thermostat to my new boiler.

The boiler (Ravenheat Little Star) only has two connections for room
stat and the stat (Drayton Digistat 3) has 3 connections.
Can anyone help with what connects to what.

I've rewired the house with no problems but this has me a bit
bewildered.

Any help would be gratefully received

Mark


--
williamsmark

(1) a common connection
(2) Call for heat
(3) heating satisfied

(I would have called 2 normally open, and 3 normally closed, but WTH?)

So I guess I'd use 1 and 3.

I presume you mean 1 and 2, unless it was an air conditioning system you
were installing...

Christian.

"Christian McArdle" wrote in
:

(1) a common connection

I presume you mean 1 and 2, unless it was an air conditioning system you
were installing...

No, 1 and 3, I remembered how confusing the instructions were so I took it
off it's mount to check what I'd done.

The diagram gives no idea - I guess it's not a standard relay but some sort
of flip flop, and they have it marked as I said.

So I'm guessing 13 what they call "call for heat" is normally closed as in
my day things were drawn in the unenergised condition. 12 "heating
satisfied" has no use in my system, I suppose I could connect a light to it
to show the boiler isn't running.
The way they've drawn the contacts the heating woulld never start.

(Who'd a thought they could make it such hard work?)

mike

So I'm guessing 13 what they call "call for heat" is normally closed as
in
my day things were drawn in the unenergised condition.

You originally said 1-2 was call for heat...

Normally, the CFH is called NO, as it is usually considered "normal" for the
heating to be off. CFH is less ambiguous.

Christian.

"Christian McArdle" wrote in
:

So I'm guessing 13 what they call "call for heat" is normally closed
as
in
my day things were drawn in the unenergised condition.

You originally said 1-2 was call for heat...

So I did, see what I mean?

Normally, the CFH is called NO, as it is usually considered "normal"
for the heating to be off. CFH is less ambiguous.

Oh well, I hope Mark's used 1 & 3 without getting electrified, and is nice
and warm

mike