Having just bought a Salus programmable wireless central heating room
thermostat I'm a little confused by the connections to the system.

I would like to simply mount the receiver unit where the old (ancient)
Satchwell dumb thermostat is as it in a good central point in a hallway
that should communicate well to all downstairs rooms.

The old one has three wires Rd, Blue and Yellow connected to three
terminals just numbered 1, 3 & 4.

The new unit has four terminals named and described in the vary basic
instruction leaflet as.
NO = Switch terminal
Com = Common switch terminal
L = Mains live
N = Mains neutral

I'm thinking the;
Blue wire goes to Mains neutral.
Red to Mains live & Common switch terminal
Yellow to Switch terminal

But am not confident hence seeking advice.

Mike

On 17/11/2018 15:35, Muddymike wrote:
Having just bought a Salus programmable wireless central heating room
thermostat I'm a little confused by the connections to the system.

I would like to simply mount the receiver unit where the old (ancient)
Satchwell dumb thermostat is as it in a good central point in a hallway
that should communicate well to all downstairs rooms.

The old one has three wires Rd, Blue and Yellow connected to three
terminals just numbered 1, 3 & 4.

The new unit has four terminals named and described in the vary basic
instruction leaflet as.
NO = Switch terminal
Com = Common switch terminal
L = Mains live
N = Mains neutral

I'm thinking the;
Blue wire goes to Mains neutral.
Red to Mains live & Common switch terminal
Yellow to Switch terminal

But am not confident hence seeking advice.


Red to L
Blue to N
Yellow to NO

And an additional short piece of wire wire from L to Com





--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 17/11/2018 15:55, alan_m wrote:
On 17/11/2018 15:35, Muddymike wrote:
Having just bought a Salus programmable wireless central heating room
thermostat I'm a little confused by the connections to the system.

I would like to simply mount the receiver unit where the old (ancient)
Satchwell dumb thermostat is as it in a good central point in a
hallway that should communicate well to all downstairs rooms.

The old one has three wires Rd, Blue and Yellow connected to three
terminals just numbered 1, 3 & 4.

The new unit has four terminals named and described in the vary basic
instruction leaflet as.
NO = Switch terminal
Com = Common switch terminal
L = Mains live
N = Mains neutral

I'm thinking the;
Blue wire goes to Mains neutral.
Red to Mains live & Common switch terminal
Yellow to Switch terminal

But am not confident hence seeking advice.


Red to L
Blue to N
Yellow to NO

And an additional short piece of wire wire from L to Com


I would want to check how the wires are connected at the other end. I
don't think that there is any standard.

The boiler may have an on/off programmer at the other end. If this goes
off the Salus may not get any power which it may not like.

On 17/11/2018 16:52, Michael Chare wrote:


The boiler may have an on/off programmer at the other end. If this goes
off the Salus may not get any power which it may not like.

There is a good chance that is the arrangement. The wireless receiver
will probably have two lights. One to indicate that it is getting mains
voltage and the other to indicate that the thermostat is calling for
heat. If there is boiler controller then the CH timing side possibly
needs to be set to be permanently on so that the wireless receiver is
always getting power and then let the thermostat control all of the
on/off and different temperature times.

Depending on the system, turning on/off the CH heating by way of the
boiler controller will also turn on/off the power to the wireless
receiver. This is very unlikely to do damage to the receiver but what
may happen is that the receiver when switched back on may not reliably
wirelessly re-pair with the thermostat.

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 17/11/2018 17:52, alan_m wrote:
On 17/11/2018 16:52, Michael Chare wrote:


The boiler may have an on/off programmer at the other end. If this
goes off the Salus may not get any power which it may not like.

There is a good chance that is the arrangement. The wireless receiver
will probably have two lights. One to indicate that it is getting mains
voltage and the other to indicate that the thermostat is calling for
heat.Â* If there is boiler controller then the CH timing side possibly
needs to be set to be permanently on so that the wireless receiver is
always getting power and then let the thermostat control all of the
on/off and different temperature times.

Depending on the system, turning on/off the CH heating by way of the
boiler controller will also turn on/off the power to the wireless
receiver. This is very unlikely to do damage to the receiver but what
may happen is that the receiver when switched back on may not reliably
wirelessly re-pair with the thermostat.

I would not want to rely on chance! The Salus may not be good at time
keeping if it loses power. I would think it would be happier to be
connected to the mains power input for the boiler.

On Sat, 17 Nov 2018 15:35:56 +0000, Muddymike
wrote:

Having just bought a Salus programmable wireless central heating room
thermostat I'm a little confused by the connections to the system.

I would like to simply mount the receiver unit where the old (ancient)
Satchwell dumb thermostat is as it in a good central point in a hallway
that should communicate well to all downstairs rooms.

The old one has three wires Rd, Blue and Yellow connected to three
terminals just numbered 1, 3 & 4.

The new unit has four terminals named and described in the vary basic
instruction leaflet as.
NO = Switch terminal
Com = Common switch terminal
L = Mains live
N = Mains neutral

I'm thinking the;
Blue wire goes to Mains neutral.
Red to Mains live & Common switch terminal
Yellow to Switch terminal

But am not confident hence seeking advice.

Mike

As you don't say what model you have, I looked on the Salus website to
find one with four terminals, e.g. the RT500RF. You will have to
consult your boiler manual to find out what the red, blue and yellow
wires have on them.

However, googling for Satchwell leads me to believe that there is
mains (not 24V) on your three wires, in which case I suggest Red to L,
Blue to N and Yellow to NO. It's not clear, but as the COM terminal is
described as "Linked live feed". it's probably already connected to L.
--
Dave W

On 17/11/2018 16:47, Dave W wrote:
It's not clear, but as the COM terminal is
described as "Linked live feed". it's probably already connected to L.


More likely com is not internally connected to live as it allows the
unit to be configured in two ways dependent on the system. If 3 wires
were removed from the terminals of the old thermostat it
suggestsswitched live and the new unit wired in the way the OP has
suggested.


--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 17/11/18 15:35, Muddymike wrote:
Having just bought a Salus programmable wireless central heating room
thermostat I'm a little confused by the connections to the system.

I would like to simply mount the receiver unit where the old (ancient)
Satchwell dumb thermostat is as it in a good central point in a hallway
that should communicate well to all downstairs rooms.

The old one has three wires Rd, Blue and Yellow connected to three
terminals just numbered 1, 3 & 4.

The new unit has four terminals named and described in the vary basic
instruction leaflet as.
NO = Switch terminal
Com = Common switch terminal
L = Mains live
N = Mains neutral

I'm thinking the;
Blue wire goes to Mains neutral.
Red to Mains live & Common switch terminal
Yellow to Switch terminal

The colours and terminal numbers are rather unrealiable and variable.
You'll be best to test which ones are Live, Neutral and control to boiler.

But essentially you are correct, if I rewrite it in those terms:

L goes to permanent live
N goes to neutral

L is linked to Com with a short piece of wire (this is pretty normal)

NO is your switched output to the boiler control (that last wire you
have left, apart from earth).


--
Email does not work

The colours you have described are the old 3 core + E and one would hope red and blue would be connected as previously described. However, that may not be the case so you must look at what those wires are connected to at the other end before you connect your thermostat.

Richard

On Sat, 17 Nov 2018 09:34:19 -0800 (PST), Tricky Dicky
wrote:

The colours you have described are the old 3 core + E and one would hope red and blue would be connected as previously described. However, that may not be the case so you must look at what those wires are connected to at the other end before you connect your thermostat.

Richard

Surely yellow was never earth? Also the old colours were red and black
not red and blue.
--
Dave W

On Sat, 17 Nov 2018 21:25:17 +0000, Dave W wrote:

The colours you have described are the old 3 core + E ...

Surely yellow was never earth? Also the old colours were red and black
not red and blue.

Did you miss the 3?

--
Cheers
Dave.

On 17/11/18 21:25, Dave W wrote:
On Sat, 17 Nov 2018 09:34:19 -0800 (PST), Tricky Dicky
wrote:

The colours you have described are the old 3 core + E and one would hope red and blue would be connected as previously described. However, that may not be the case so you must look at what those wires are connected to at the other end before you connect your thermostat.

Richard

Surely yellow was never earth? Also the old colours were red and black
not red and blue.


Red blue and yellow for old 3 phase cable, including triple and earth.
The earth was bare, or sleeved in G+Y (or green if you go back far enough).

--
Email does not work

On 17/11/2018 17:34, Tricky Dicky wrote:
The colours you have described are the old 3 core + E and one would hope red and blue would be connected as previously described. However, that may not be the case so you must look at what those wires are connected to at the other end before you connect your thermostat.



Assuming everything is what it should be (the OP has actually said that
it is) then the blue core should have been oversleeved with black and
the yellow core should have been oversleeved with red.

I have seen it happen a couple of times out of thousands of
thermostats/bathroom fans etc I have looked at/replaced/worked on.

I might have oversleeved the yellow with red a few times but I never
oversleeved a blue with black.






--
Adam

ARW wrote:

On 17/11/2018 17:34, Tricky Dicky wrote:
The colours you have described are the old 3 core + E and one would hope
red and blue would be connected as previously described. However, that
may not be the case so you must look at what those wires are connected
to at the other end before you connect your thermostat.



Assuming everything is what it should be (the OP has actually said that
it is) then the blue core should have been oversleeved with black and
the yellow core should have been oversleeved with red.

I have seen it happen a couple of times out of thousands of
thermostats/bathroom fans etc I have looked at/replaced/worked on.

I might have oversleeved the yellow with red a few times but I never
oversleeved a blue with black.

If the blue wire goes back to mains neutral why does it need
oversleeving in black? Is it because the rest of the wiring may be
still in the old colours? Couldn't you oversleeve the yellow and red
with brown? Sorry, genuine ignorance here.

--

Roger Hayter

On 22/11/2018 15:52, Roger Hayter wrote:
ARW wrote:

On 17/11/2018 17:34, Tricky Dicky wrote:
The colours you have described are the old 3 core + E and one would hope
red and blue would be connected as previously described. However, that
may not be the case so you must look at what those wires are connected
to at the other end before you connect your thermostat.



Assuming everything is what it should be (the OP has actually said that
it is) then the blue core should have been oversleeved with black and
the yellow core should have been oversleeved with red.

I have seen it happen a couple of times out of thousands of
thermostats/bathroom fans etc I have looked at/replaced/worked on.

I might have oversleeved the yellow with red a few times but I never
oversleeved a blue with black.

If the blue wire goes back to mains neutral why does it need
oversleeving in black? Is it because the rest of the wiring may be
still in the old colours? Couldn't you oversleeve the yellow and red
with brown? Sorry, genuine ignorance here.


I just left the old colours as is and found a piece of red to bridge
across to the com.

Mike

On 17/11/2018 17:24, Tim Watts wrote:
On 17/11/18 15:35, Muddymike wrote:
Having just bought a Salus programmable wireless central heating room
thermostat I'm a little confused by the connections to the system.

I would like to simply mount the receiver unit where the old (ancient)
Satchwell dumb thermostat is as it in a good central point in a
hallway that should communicate well to all downstairs rooms.

The old one has three wires Rd, Blue and Yellow connected to three
terminals just numbered 1, 3 & 4.

The new unit has four terminals named and described in the vary basic
instruction leaflet as.
NO = Switch terminal
Com = Common switch terminal
L = Mains live
N = Mains neutral

I'm thinking the;
Blue wire goes to Mains neutral.
Red to Mains live & Common switch terminal
Yellow to Switch terminal

The colours and terminal numbers are rather unrealiable and variable.
You'll be best to test which ones are Live, Neutral and control to boiler.

But essentially you are correct, if I rewrite it in those terms:

L goes to permanent live
N goes to neutral

L is linked to Com with a short piece of wire (this is pretty normal)

NO is your switched output to the boiler control (that last wire you
have left, apart from earth).


Thanks for the confirmation guys.Its wired as per and fully functioning.

Mike