Upgrade analogue thermostat to Worcester Easy Control

24 Oct 2013
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United Kingdom
Wondering if anyone can help please.

I have what I believe to be an S plan central heating system, consisting of:

Worcester Greenstar 27Ri boiler
Horstmann h37xl programmer
British Gas RS1 room thermostat
Danfoss zone valves x2
Honeywell wiring centre
Telford stainless sealed hot water tank (connected to solar panels)

I have bought a Worcester Easy Control CT200 and a Worcester Easy Control Adapter.

The CT200 talks to boiler via EMS and I have successfully had it controlling temperature. However, I figured this is probably dangerous on its own as the zone valves do not know position as not connected to easy control. Easy control with the adapter can switch an A/C load (guessing a zone valve) but I am beyond my comfort zone in which wires to tap into.

I am an electronics specialist but heating and plumbing is not something I know much about.


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Much depends on the plumbing, if the by-pass valve can allow water to circulate when the zone valves are closed, they there will not be a problem as to damage.

I am just an electrician, and I also have a possible problem that TRV's could all be closed when the boiler runs, I am not sure I need a zone valve, however before fitting I was getting reverse flow when only one pump was used, but likely the better cure would have been go to one pump instead of two.

I would re-post in Plumbing section, clearly needs a zone valve for domestic hot water, not sure if it needs a zone valve for central heating, the TRV's should do that.

I did look at the idea of ebus thermostats, but my boiler is oil so does not modulate, but the point is my home has internal doors, so any wall thermostat needs to connect to the TRV's or other temperature senders, only in a open plan home, or using hot air circulation can a single wall thermostat work, in the main if not interconnected they are only to turn off heating on warm days, which is why my own Nest Gen 3 is rubbish in my house.

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