Wiring new Salus EP200 with RT500RF room stat

27 Jun 2015
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United Kingdom
Hello, I need some help please with wiring my CH and DHW.

What I hope to achieve is a system whereby I can program both my CH and DHW independently, both times and temperature. Previously I had just the option of CH + DHW or DHW only. I only had 1 x 2 port valve but am going to fix a second to allow CH to be off when DHW is on - primarily to reduce the temp of the DHW and hopefully reduce oil usage!

i.e. CH set to temp of boiler (say 70 degrees) and controlled by programmable room stat and DHW to be heated to a set temp controlled by timed program and cylinder stat (60 degrees or lower)

The components I have are

1 x Salus EP200 2 channel programmer

(Connections are N , L , 1 HW OFF, 2 CH OFF, 3 HW ON, CH ON, Earth)

1 x Salus RT500RF wireless programmable room thermostat

(Connections are NO ,COM, L , N)

1 x Salus CT100 cylinder stat

(Connections are NO ,COM, L , N)

1 x Salus TC100 wiring centre

1 x 2 port motorised valve with 3 connections N, L & E

1 x 2 port motorised valve with 5 connections N, L , E , C – CH Call, CH (NO)

Feed to the oil boiler and pump wired to both be on at the same time from the same N & L feed

I had hoped the wiring centre would make life easier but all the wiring examples I’ve looked at have confused me particularly as they all show the 2 port valves as having 5 connections when my original one, controlling CH, has only 3!

I’m hoping this is a simple wiring job for the experts here and that some of you kind folks will point me in the right direction.

Thank you
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Update! I have looked more closely at the original 2 port valve and although only 3 wires were originally connected there are 5, the orange & grey weren't connected to anything.

The wiring for the RT500RF shows COM linked to L but I think I need to wire COM to CH ON on the EP200 and NO to CH 2 port L
Does this make sense?
You dont need to connect the ch to the ep200, the rt500 now controls the ch, link L and NO in the rt500 and COM to the brown of the ch 2 port, not sure why they have done it that way round but it does not make any difference as its just a switch.
I think you are trying to achieve a fully pumped s-plan system but can't see from here how it's been plumbed.

The orange and grey wires are the relay wires to switch on boiler and pump and will be needed if more than one zone valve is present.

A bit of googling on terms such as s-plan, c-plan etc should find your answers but do make sure the hydraulic and electrical layouts are compatible.

Edit, 'simultaneous' post although I took ages over it, unfortunately can't see the thread when in preview mode with the new forum software.
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Thank you both for your kind and prompt replies and advice. All wired in and working well.
I'm really glad I got the wiring centre now as it made the wiring so much easier and neater!

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