"TW" wrote in message
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"xena" wrote in message
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"xena" wrote in message
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"Set Square" wrote in message
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In an earlier contribution to this discussion,
xena wrote:


The RTS1 is an electronic stat and requires a neutral to work. I'm not
sure whether the relay is actually normally closed so if the neutral is
not there, it never switches off.

Are you sure that the blue is in the neutral and not the switched live
terminal?

Blue is definitely in neutral. There is nowt in the switched live.

It's possible that if the blue wire is in the neutral terminal, and it is
really the switched live that the stat is in series with the pump but I
would expect the resistance of the stat electronics to be too high for
that to work.

What wires are in what terminal numbers?

There is only one numbered terminal, that 3 (call for heat). There's
nothing in there.

Um, how significant is the fact that the heating is on?? Does it mean
that I need a weird reversed thermostat?!

No, the fact that the heating stops when the stat is removed from the
backplate means that the wire is call for heat.


The type of stat which you have *needs* 4 wires, and can't safely be
installed with 3. A common short-cut employed by some plumbers is to
use the
green/yellow wire for the switched live (which you refer to as the
"call to
heat"). This is unsafe for two reasons. Firstly the stat needs to be
eathed,
but isn't when this is done. Secondly, a wire which any reasonable
person
would expect to be earthed is, in fact, live!

TBH, the thermostat is plastic cased, and if I sleeve the wires with the
correct colours, would this be so bad? After all, the rest of the wiring
is likely to be to the same standard and I'm not replacing the lot as the
house is for sale!

I'm pretty sure the RTS1 is double insulated so you "could" do this, It's
bad practice though.

Yes the instructions say that it is double insulated.


Drayton Digistat does not need a neutral (it has a battery) and will fit
on the same backplate.