Two pump multiple zone wiring diagram with pump overrun and mid position valve

[craigskelly]

I had an original central heating/hot water system incorporating a single pump, single room stat and a mid-position valve. I have now built an extension and extended the heating system so that I have 2 pumps and an additional 3 zones each controlled with its own valve and stat. There is a single Potterton EP2 programmer which controls both systems.
I wired and tested the new system as a standalone entity and it worked fine but I am having a few issues when I integrate both systems which in the main appear to work correctly except when I need to boost the heat outside normal operating times. When I do this I have found that I need to "boost" the hot water as well in order to get the heating to come on. I have a number of relays controlling the system including one used for pump overrun and there must be a simple wiring issue but rather than me spend a lot of time fault finding/checking through my drawings, does anyone have a wiring diagram that would suit my setup i.e. multiple zones, two pumps, single controller, mid position valve, pump overrun feed? I would have posted my drawings here but they are not in a format (at the moment at least) to be able to do that.

 

[Ermintrude]

Upload photo

 

[craigskelly]

The problem is Ermintrude that a have a series of drawings that will only make sense to me at the moment as I haven't integrated them yet - some are little more than scrawls. I am an electrical engineer so will be able to work my way through this but I have come up with the design from scratch and it would probably have been easier to request a copy of a proven design at the beginning. Hopefully someone will see this post and will send me a suitable drawing!

 

[Dannyparty92]

Should have gone with an S plan plus.

 

[kris]

Hi there mate, it sounds like you've a simple enough system I take it you've now zone 1 existing heating zone 2 extension and zone 3 hot water ?? Or is it upstairs , downstairs and hot water , .? You say you've 1 controller, i take it its 3 channel ?
Wed need more info before hazarding a guess but I'd look at the programmer if the issues only when advancing,

 

[craigskelly]

Kris,
I have a zone for hot water, a zone for the old pre-extension heating plus another three for the new extension. The latter three zones are on a separate pump. With regards to the controller, I assume you would class it as 2 channel (hot water + heating). I did have an issue with the old controller which was randomly simultaneously send 220V out on the HW OFF and HW ON at the same time - I couldn't work out why the boiler kept operating in the middle of the night for the hot water - anyway, I solved that problem by changing out the controller.
Looking on the net today, I seem to have a Y Plan setup or perhaps more aptly a Y Plan Plus!!!!
I believe I only have the problem with the advance as during timed periods the HW and CH are on for the same time. Guess this means the CH is relying on the HW to provide 220V to my relays somewhere!
I think I will just have to carry on making my way through the wiring diagrams - I have found one issue already!

Danny,
Yes, may have been easier to go with an S Plan Plus!!