Converting a Honeywell S-Plan two zone to three zone system

2 Dec 2010
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United Kingdom
Hi I wonder if anyone can provide some advice?

I'm in the process of slowing converting a two zone system (CH & HW) into a three zone system separating upstairs and downstairs CH (as the pipework joins up rather neatly in the boiler cupboard).

I had the system re-flushed recently and had the plumber install a third V4043H valve while the system was empty. I then wired the third valve in parallel with the existing CH so I still have a two zone system for now.

My intention is to get a third thermostat for upstairs (probably a Salus RT300RF) and then later replace the programmer with a three zone job (like the TimeGuard TRTO-38).

My only issue is that I'd prefer to use a wiring centre rather than a complicated mess of terminal blocks.

I currently have the honeywell 42005748-001 wiring centre but does anybody know if there is a equivalent wiring centre for three zones?

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Buy an electrical enclosure with DIN rail.

You can then clip on as many connectors as necessary.
In my opinion the most useful wiring centre is the Drayton LWC1.

When you get the zone 2 heating working you will merely need one more terminal for the brown wire on the new valve to be separated, all the others are common.

I use a spare way in the LWC1.

We would not usually use a three way timer, we specify Honeywell CM range programmable room stats for each zone of heating, and use a simple one channel programmer, such as the Honeywell ST9100C, for the Hot Water.

If you have a two channel HW/CH programmer, buy two nice prog stats and leave the programmer as is. Personally, I think the Salus stuff is a bit cheap and tacky but perhaps I am just a Honeywell tart.

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