Joules ASHP - Controls for towels rails & rads + UFH

[Andehh]

As part of our property we specced UFH in two zones....then towels rails, and separate radiators in the garage (for a future potential grannie annex/working in the garage in the winter - garage is insulated) - so 4 circuits that all teminate in the plant room, each with their own zone value.

 

The 2 x UFH zones are plumbed off the ASHP outputs 1 and 2, then the 3rd output feeds a pipe which splits into the towel rails & garage rads via a sort of split pipe, then each has its own zone value zone valve on it (not wired up right now). What I expected was for the towel rail circuit & garage radiators circuit to be on two separate loops (as they are), with the ability to control them individually. We have a stat in the garage (grannie annex...) and then I asked for a timer for the towel rads.

 

Builder/his team are scratching their heads & don't think it can be done, Joules arn't being overly interested and just 'suggest' their system only support 3 zones and therefore towels & garage must be on one. I cant help but think there must be a way for each of the 2 zone values (rads + garage) to independently open 'their circuit' and call for heat, for the ASHP's 3rd output to release the heat and down the right circuit it goes?!

 

Does anyone know of  work around where the zone value for the Towels & garages can independently call for heat, without both actuating? (other then manually isolating them)

 

thanks!

[JohnMo]

If you just have towel rads on a separate control circuit, you will need a good sized buffer for your heat pump to stay happy.

 

Why aren't you running weather compensation on a single zone?

 

Keep it simple.

[Andehh]

We have 3 large towel rails on large pipe runs, but short cycling is a risk. They'd only ever be used for a burst of warmth to warm towels as anything more and we'd over heat the rooms. 

 

The rads in the garage are significantly over sized.

 

We had an electrician & plumber that were all to happy to fit first, charge us then ask questions later & suggest what we did was daft....this being the example of over complicated plumbing that the plumber never thought to educate us on (ie charged for all the pipes, zone valves and fitting.... Then declared he doesn't think it will work). Wish I'd found build hub in time....!!

 

We do run weather compensation on Samsung Gen6 controller.

 

Ambition is UFH is all individually zoned per room BUT controlled as two big zones (basically two sides of a large bungalow, with a small central entrance hallway) - bedrooms kept slightly cooler (19 degs ish) then the kitchen/lounge areas (21 degs ish).

 

Just seeing if there is way of controlling the circuits individually off the single joules "3rd output". 

Edited August 14, 2023 by AliG
Post referred to was deleted

[Andehh]

Pics of what It looks like.... 

 

You can see the top pipe above heating zone 1 and heating zone 2 (from the joules controller) goes down and splits into the two feed to rads and towel rails, with the 2 zone controllers in line with each.  Wiring for these zone valves disappears into the controller. I suspect wired together so they both open and close together?

 

But then I have a thermostat in the garage, which I assume controls this circuit. Electrician didn't say he was planning on wiring a timer for the towel rails... But I don't know how this would interact with the garage stay (other then double control it??)

 

Edited August 14, 2023 by Andehh

[Andehh]

Just a shot in the dark if anyone has any ideas? 

 

Worse case I will just use the manual circuit isolators plumber installed to manually shut off flow to garage if we want towel rails, and then do the same for towel rails when we want to use garage. Garage thermostat is wasted then, but can blank it until/if we ever use it as a grannie annex (and accept we lose the towel rails), and just use a timer to control the towel rails. 

 

(Until then we'll use towel rails for a 30min timed cycle to warm towels each even to prevent short cycling.) 

Edited August 15, 2023 by Andehh

[JohnMo]

Think running towels rails only from a heat pump is daft irrespective of the buffer size.  Make then dual fuel, with an electric element.  In the heating season run them with the rest of the heating system and any other time on the electric element.

[Beelbeebub]

OK shot in the dark. 

 

The Joules cylinder controller has 3 zones. 

 

You close a circuit (thermostat) on z1 and it does the necessary, opens the appropriate zone valve, calls for hear from the HP etc. 

 

If you do the same with Z2, it all happens with Z2 etc. 

 

And same with Z3. 

 

Can you not wire up ZG (garage) and ZT(towel rail) valves to their respective zone valves and then have the microswitch in those zone valves wired in parallel to the Z3 input. 

 

ZT and ZG are fed from Z3. 

 

The if ZT is called for, the ZT valve will open, and also close the switch calling Z3 which activates opens Z3, calls for heat. The food then goes down the ZT loop

 

Likewise for ZG. 

 

That said I agree with @JohnMo prob best just to use electric elements to heat the towel rails if you need them outside of central heating times. 

[Andehh]

Yep sadly we've moved in to the now-completed house, so are stuck with what we put on the drawings, which trades followed to the letter only to then look blankly when I asked them to show me how it worked. 

[Andehh]

48 minutes ago, Beelbeebub said:

OK shot in the dark. 

 

The Joules cylinder controller has 3 zones. 

 

You close a circuit (thermostat) on z1 and it does the necessary, opens the appropriate zone valve, calls for hear from the HP etc. 

 

If you do the same with Z2, it all happens with Z2 etc. 

 

And same with Z3. 

 

Can you not wire up ZG (garage) and ZT(towel rail) valves to their respective zone valves and then have the microswitch in those zone valves wired in parallel to the Z3 input. 

 

ZT and ZG are fed from Z3. 

 

The if ZT is called for, the ZT valve will open, and also close the switch calling Z3 which activates opens Z3, calls for heat. The food then goes down the ZT loop

 

Likewise for ZG. 

 

That said I agree with @JohnMo prob best just to use electric elements to heat the towel rails if you need them outside of central heating times. 

 

Thank you for this suggestion, my non electrician head sees the logic in this, and I guess it's the sort of thing I'd like to achieve.... Just playing that back in my layman's view of it... I presume you mean thermostats calling for heat on their respectively zone valve, but with the zone valves wired in parallel when one calls for heat and actuates, it shuts the other off? 

 

If neither call for heat, would that mean both shut off though? 

 

Welcome others thoughts on the possibility of this working? 

 

Electrician back on Thurs and Fri for last time so would like to throw a few ideas at him!

 

Thank you

Edited August 15, 2023 by Andehh

[TonyT]

You need to draw the existing set up as a schematic so people can see how it’s plumbed, and a little story( control philosophy ) on how it works, ie press heating controller button one and x valve operates and boiler fires up. That kind of idea. Let’s people see what you have got, what’s possible to change/alter.

 

everything is possible it just needs space/time/money/right people

[Andehh]

Sorry, not sure how much this helps but this is how it is plumbed into the Joules ASHP.... pics above shower the 3 x zone valves for the rads/Towel rails... 

[ReedRichards]

Can you not use a third party controller to split one of your zones into two?  

[Beelbeebub]

1 hour ago, Andehh said:

 

Thank you for this suggestion, my non electrician head sees the logic in this, and I guess it's the sort of thing I'd like to achieve.... Just playing that back in my layman's view of it... I presume you mean thermostats calling for heat on their respectively zone valve, but with the zone valves wired in parallel when one calls for heat and actuates, it shuts the other off? 

 

If neither call for heat, would that mean both shut off though? 

 

Welcome others thoughts on the possibility of this working? 

 

Electrician back on Thurs and Fri for last time so would like to throw a few ideas at him!

 

Thank you

The 2 port valves are spring loaded. No power to them they are closed. 

 

If you put 240v across them, the motor opens the valve. Asong as 240 v is on the valve the motor apply torque and the valve stays open. 

 

When the valve opens a cam inside pushes a microswitch and turns it on. 

 

So you wire your valve up to 240v, with the thermostat as a switch. When the thermostat calls for heat, it closes the circuit, 240v is put across the motor which opens the valve.  The microswitch is wired to the bit that demands the boiler (or in this case the HP). 

 

If your garage thermostat demands heat, it closes, garage some valve opens and the valve microswitch calls for heat. 

 

If your towel rail timer calls fo heat, it closes, towel rail valve motor actuate, opens valve and closes the microswitch calling for heat. 

 

Basically if any zone valve is actuated the boiler/HP is called to provide heat.