Intergas X-plan with two zones

[MNW67]

I've spoken with tech support and my local Intergas expert. Neither were 100% sure whether you could do the PDHW X-Plan with two zones. Tech support found a diagram which they thought might do it but it was marked strictly for internal use only.

I understand the general idea where the boiler sends a signal to the HW zone valve which then sends a signal to close the NO CH valve. What I can't see on the wiring diagram is what would control the two other valves which operate the two heating zones.

 

[CBW]

Have a look on this website: https://heatingacademynorthampton.co.uk/pdhw/

 

[MNW67]

The official Intergas X-Plan wiring diagrams all seem to show it using OpenTherm. But I think I've just read something from the top Intergas technical bod which says you can use the switched live instead. That would make X-Plan with two zones easy, I think. But it would be nice to know whether it can also be done when using OT. That would be the best scenario.

 

[MNW67]

Have a look on this website: https://heatingacademynorthampton.co.uk/pdhw/

Thanks for that. There's a lot to take in. But it makes PDHW sound a lot more flexible than I had previously realised.

 

[MNW67]

I thought it might be useful to show the diagram I am looking at which covers the HRE boilers. It's just so different to what I am used to.

 

[BlueLoo]

Why bother with CH zone valves?

 

[MNW67]

Fear of change, probably. Also cost. Paying for twenty smart TRVs to be fitted wouldn't be cheap. We have a very simple system which works very well for our house and lifestyle. Plus, I have often found teaching people to use even very simple controls can be a massive pain!

 

[BlueLoo]

Fear of change, probably. Also cost. Paying for twenty smart TRVs to be fitted wouldn't be cheap. We have a very simple system which works very well for our house and lifestyle. Plus, I have often found teaching people to use even very simple controls can be a massive pain!

Get that.

However, my family love it.
They control their own spaces with the twist of the rad valve.
20 rads means lots of rooms.
Having even half on them on a standby temp when not used saves a huge amount.

Also, i think the above (zero zone) works very well with home insulation improvements.
The more you reduce heat loss, the more stable the rooms become and the less blasting of rads you need.
Also means less stress on the boiler as it only heats where needed.

I have 12 rooms fully controlled.
Nobody finds it a problem.

But, if you can afford to heat full floors at a time, drive on. It's a personal thing.

My gas bills have reduced so much that i am now a grand in credit (12 months on) with my gas company and the bill-spread contact I'm on.

 

[MNW67]

I've read that link. It's fantastic. Is it the case that most OpenTherm capable thermostats will only send one signal. Either on the OT connection or on the SL? But EPH controls can send a signal on both. Which is why they can be used to control a zone valve whilst also using OT?