Room thermostat

[no1kingfrog]

Hi

I currently have a Honeywell room stat fitted that i need to replace.
The stat has 3 wires - red, black and unsheathed.

I want to fit another room stat (Sunvic TLX 4101) connection block is
numbered 1, 2 and 3.

Cannot understand the wiring diagram or what is 'com' , 'dem' and
'sat' .

It shows com is 2, dem is 1 and sat is 3.

Any assistance appreciated


Fred H

 

[IAN CAPEL]

I believe the sunvic has different wiring to the honeywell. The wires you
have to the honeywell are earth( unsheathed) with the other two being live
in and live out when the thermostat operates. The sunvic would require a
live and neutral in with a switched live out so you would need to run
another wire. The easiest way to do it is to get a thermostat that would
replace the honeywell as a one for one

 

[Mathew Newton]

I believe the sunvic has different wiring to the honeywell. The wires you
have to the honeywell are earth( unsheathed) with the other two being live
in and live out when the thermostat operates. The sunvic would require a
live and neutral in with a switched live out so you would need to run
another wire. The easiest way to do it is to get a thermostat that would
replace the honeywell as a one for one

Why would the Sunvic need a neutral? I'm not familiar with said device
but from what the OP says about the terminal markings it doesn't.

Com = Common (Live In)
Dem = Demand - Will be connected to Common when there is a demand for
heat (Switched Live Out in this case)
Sat = Satisfied - Will be connected to Common when there is no demand
for heat (Leave disconnected)

Mathew

 

[no1kingfrog]

Thanks for the assist. will try find another Honeywell

 

[The Natural Philosopher]

Why would the Sunvic need a neutral?

Some thermostats draw a little current when 'off' - something to do with
reducing switching delays.

 

[Mathew Newton]

Some thermostats draw a little current when 'off' - something to do with
reducing switching delays.

In which case it would have a terminal marked for such.

Mathew

 

[Mathew Newton]

Thanks for the assist. will try find another Honeywell

There's nothing wrong with the Sunvic you've purchased! Both your
Honeywell and Sunvic are 2-wire stats (disregard the 'sat' connection
as an apperent third - it's not).

Connect Red to Com (2), Black to Dem (1), and the unsheathed cable
(which ought to have a green/yellow sheath on it but often don't) to
the Earth terminal (if provided) or secured out of the way. Don't chop
the earth just because it may not be required for this stat - the next
replacement may need it. Leave the Sat (3) terminal not connected.

Mathew

 

[The Natural Philosopher]

In which case it would have a terminal marked for such.

Mathew

Yes, The Neutral.

 

[The Natural Philosopher]

On Sun, 02 Apr 2006 09:35:10 +0100 someone who may be The Natural


Some mechanical thermostats have an accelerator heater, which needs
a neutral wire. The heater is on when the thermostat is calling for
heat. Thus it switches off earlier than it would otherwise do and
thus reduces overshoot. Electronics can do the same thing
mathematically.

Ah, I stand corrected. I know all mine are like this anyway.

How does one stoop them making 'orrible thee second arcing noises too..

We lose the TV completely when some cut in and out..never Id'ed which
ones tho.

 

[Dave Stanton]

How does one stoop them making 'orrible thee second arcing noises too..

We lose the TV completely when some cut in and out..never Id'ed which
ones tho.

They should have components to stop this, normally a capacitor/resister
stubber network. Maybe if they are old the caps have failed.

Dave

 

[Mathew Newton]

Yes, The Neutral.

What Neutral?! It's got a 'common', 'demand' and 'satisfied' - nothing
else!

Mathew

 

[The Natural Philosopher]

They should have components to stop this, normally a capacitor/resister
stubber network. Maybe if they are old the caps have failed.

Dave

They all did it from new..

 

[The Natural Philosopher]

What Neutral?! It's got a 'common', 'demand' and 'satisfied' - nothing
else!

In which case, its not one that needs a neutral is it?

 

[Mathew Newton]

They all did it from new..

Are they electronic or mechanical (i.e. bimetallic strip)? As Andy
hinted, electronic ones will likely be far better in this respect.

Mathew

 

[Mike]

Many thanks to all for having this conflab as it's answered all the
questions I had - same as OP really except my original was a Satchwell
TLX 2203. Somewhat annoying that the Sunvic website doesn't recognise
the existance of the TLX 4104!
Mike

 

[Trev1]

Good evening
, I currently doing some DIY and replacing the sunvic dail thermastat for a tado wired thermostat.. hit a bump in the road , the sunvic as 2 wires , brown one going into terminal 1 amd a black one going into terminal 2.
When I attach the tado am I right saying the brown wire to go to com and black wire to NO( not open)

 

[KenGMac]

Have you had a look at U-Tube, find the Stat you have and all [should] be revealed???

Ken.