Heat Only Boiler + S Plan+ + Weather Compensation Query

magician2905 · Apr 11, 2023

Hi looking for some advice here if anyone would be so kind.

Our existing system consists of an Ideal Logic Heat H15 heat only boiler paired to a 180L Kingspan Tribune XE Unvented Indirect Hot Water Cylinder (this is the Dual Stat version).

Zone 1 (Downstairs) consists of 7 Radiators + Plumbed Plinth heater, Zone 2 (Upstairs) is 6 Radiators. All radiators have manual TRV heads apart from 1 in each zone.

The boiler supplies both HW and CH and is controlled by a Drayton Wiser Kit 3 Controller that has individual time schedules for Hot Water production and Zone heating temperature & times.

On the Logic Heat H15 the "SET" temperature dial (E = 67'C) determines the temperature for both the CH and HW and has to be set to a minimum of 64'C so that the hot water is actually still hot enough when it comes out the taps.

This doesn't seem to be particularly efficient as we are driving the radiators too high just so that we can maintain out hot water temp.

We are considering adding Weather Compensation to the boiler.

Doing this we can then set the appropriate curve for the heating and this would then use, one of, the Cylinder Thermostats to control the temperature of the hot water production which seems a more efficient way to use the boiler?

So the query is would we be able to retain our 2 Zone heating setup? The upstairs zone is rarely on so losing that function would be less than ideal.
Would we still be able to continue to use the Drayton Wiser Controller and Zone Thermostats or would we need some other controller setup?

The Opentherm stuff is a red herring it only works with certain Combination Boilers unfortunately.

Look forward to your assistance.

gmartine · Apr 12, 2023

Dual stat or dual immersion, is the cylinder stat is set correctly?

ShaunCorbs · Apr 12, 2023

Sorry to say no, not on a heat only you would need to change the boiler to a system eg vouge system boiler and hope you have a spare core etc

magician2905 · Apr 12, 2023

gmartine said:
Dual stat or dual immersion, is the cylinder stat is set correctly?

Dual Stat, Single Immersion.

One controls the electric Immersion itself.

I am led to believe that the second stat can be used to call for heat from the boiler (so would take over in the event we installed weather compensation) or in a different boiler configuration.

Our last house had an open vented system, heat only boiler, with the old style cylinder and a cut out in the insulation for the cylinder thermostat which then controlled the DHW.

magician2905 · Apr 12, 2023

ShaunCorbs said:
Sorry to say no, not on a heat only you would need to change the boiler to a system eg vouge system boiler and hope you have a spare core etc

Shaun thanks for reply.

Haven't got a scooby (clue) what you are referring to when you talk about a spare core

I am trying to get my head around the reasoning so can I ask why you think that changing to a System Boiler would be necessary.

A System Boiler is predominately a Regular (or Heat only) boiler with an internal pump rather than an external pump. I appreciate different boilers types/models/brands have more built in features than the crappy Logic Heat H15 which is essentially a giant gas fired kettle.

On the flip side this also means that "the "brains" of the H15 are essentially external (in our case a Wiser Kit 3) and the zone valves themselves don't care where the signal to open or close comes from as long as there is a call for heat from somewhere.

The Cylinder Stat controls the call for heat for the HW, either constantly or on a schedule (using some kind of timer which can either be completely dumb ie mechanical pins or something more advanced)
- That's Zone Valve 1 (normally open?)
The Weather Compensation Kit automatically controls the call for heat/temperature of the CH based on it's setpoint?
- That's Zone Valve 2 (normally closed?)
A secondary Thermostat placed upstairs (currently its in the master bed) is set to say 10'C - which is off in our case (in fact 14'C is about the baseline temp through winter).
If we decide we want to heat upstairs we turn this Thermostat up, to say 18'c, which then opens Zone Valve 3 (normally closed?). Wouldn't this work as long as the weather compensation is calling for heat already?

I hope that makes sense?

ShaunCorbs · Apr 12, 2023

Because when it’s warmer the cylinder would only get to 30 ish degrees so you would have to use the immersion also there’s no wc kit available for a heat only boiler for this reason

The vogue boiler has two switch lives one for the cylinder and another just for heating so you can have different temperatures etc

magician2905 · Apr 12, 2023

ShaunCorbs said:
Because when it’s warmer the cylinder would only get to 30 ish degrees so you would have to use the immersion also there’s no wc kit available for a heat only boiler for this reason

The vogue boiler has two switch lives one for the cylinder and another just for heating so you can have different temperatures etc

Oh, now I understand.

There is a Weather Comp kit for the Ideal Logic Heat H15 - details below:

The HW then becomes controlled by the Cylinder Thermostat. As previously noted the Kinspan Tribune XE Indirect Unvented Cylinder has 2 Thermostats - one for the electrical Immersion heater and the second is unused in our current config but would be used when adding the weather comp kit to the install.

Just add www to these.

idealheating.com/products/weather-compensation-kit

idealheating.com/uploads/documents/Weather_Compensation_Kit_User_Guide.pdf

This kit is suitable only for the domestic gas boilers listed below:
Note
1. A timer should be fitted to the system so that CH will be switched off when appropriate
2. The Connector (Frame 1, item C). is prefitted to certain boilers. Boilers that don't have this fitted are marked with an * on page 2.

HEAT BOILERS
Logic Heat
Logic Heat H
Logic+ Heat
Logic Max Heat

COMBI BOILERS
*Logic Combi
*Logic Combi C
IE Logic Combi ES
Logic Code Combi ES
Logic+ Combi
*Independent Com
*Independent+ Com
*i-mini C Vogue
Combi C GEN2 Vogue
Combi C IE GE
Logic Max Combi C
Vogue Max Com
SYSTEM BOILERS
Logic System
Logic System S
Logic+ System
Vogue System S GEN2
Vogue System S IE GEN2
Logic Max System S Vogue Max System

ShaunCorbs · Apr 12, 2023

If you look at the diagram it requires two switch lives eg picture 1

To my knowledge they only have one well the old ones did unless they’ve updated for the newer model might be worth a check on yours first

magician2905 · Apr 12, 2023

ShaunCorbs said:
If you look at the diagram it requires two switch lives eg picture 1

To my knowledge they only have one well the old ones did unless they’ve updated for the newer model might be worth a check on yours first

That's the same Wiring Diagram shown in the current Weather Comp instructions but on page 7 goes on to say

ShaunCorbs · Apr 12, 2023

Yes so normal heating sl 1

Cylinder demand sl 2

Wc is used if sl1 is calling

But goes to full rate if sl2 is calling you need to know if you have 1 or 2 sl terminals

magician2905 · May 1, 2023

ShaunCorbs said:
Yes so normal heating sl 1

Cylinder demand sl 2

Wc is used if sl1 is calling

But goes to full rate if sl2 is calling you need to know if you have 1 or 2 sl terminals

Hi Shaun (or anyone else reading this)

I finally understand what you were referring to and have an update......

There is no SL2 wire or spare wires installed......

Ideal Halo kit would solve the issue but that's looking like it will cost £420 + fitting!!!! And only works with Ideal equipment.....

Can we use this from EPH - EPH Transceiver Pack to create a wireless solution? Options 4 & 5 create a two way communication system - one (4) is 240V whilst (5) is Volt Free. I am going to assume that this would be 240V as its on the "Left Hand Side" and has nothing to do with connecting to either Opentherm or Weather Comp which are on the "Right Hand Side"

gmartine · May 1, 2023

If I read your query correctly your boiler (regular) can still only fire at one set temp so how does a wireless connection help you? Your boiler still requires an ability to run at two temperatures the heating circuit at a much lower temp than the HW circuit.

ShaunCorbs · May 1, 2023

Yes it will work but most of the time it’s easier and more reliable to install a new wire

As for wiring it’s stnd 240 no low voltage as it’s just switches etc I would use that for the hot water side

magician2905 · May 1, 2023

gmartine said:
If I read your query correctly your boiler (regular) can still only fire at one set temp so how does a wireless connection help you? Your boiler still requires an ability to run at two temperatures the heating circuit at a much lower temp than the HW circuit.

Adding Weather Compensation decouples the Boiler Firing Rates (kw) for CH and DHW.
For CH it fires and modulates based on the curve set for the weather compensation.
For DHW it fires @ maximum rate of 15kw based on calls for heat from Programmer then Cylinder Thermostat.
However as Shaun had noted (which I hadn't completely understood) that this function requires an additional Switched Line to allow the boiler to facilitate this.
You might wonder why not just run additional wires.... Well first the wires go into the wall (behind the plasterboard) across the ceiling to the other side of the room then to about the middle of the kitchen/diner underneath where the Cylinder and Wiring Centre are all installed on the first floor. The house is less than 3 years old so unlike older house with floorboards has T&G Chipboard floors requiring a lot of mess/remedial works just to run in a couple of wires.
Hence the need for some way to wirelessly switch this from the boiler to the wiring centre and, presumably, back again.

ShaunCorbs · May 1, 2023

magician2905 said:
Adding Weather Compensation decouples the Boiler Firing Rates (kw) for CH and DHW.
For CH it fires and modulates based on the curve set for the weather compensation.
For DHW it fires @ maximum rate of 15kw based on calls for heat from Programmer then Cylinder Thermostat.
However as Shaun had noted (which I hadn't completely understood) that this function requires an additional Switched Line to allow the boiler to facilitate this.
You might wonder why not just run additional wires.... Well first the wires go into the wall (behind the plasterboard) across the ceiling to the other side of the room then to about the middle of the kitchen/diner underneath where the Cylinder and Wiring Centre are all installed on the first floor. The house is less than 3 years old so unlike older house with floorboards has T&G Chipboard floors requiring a lot of mess/remedial works just to run in a couple of wires.
Hence the need for some way to wirelessly switch this from the boiler to the wiring centre and, presumably, back again.

Do you have down lights eg spot lights ?

magician2905 · May 1, 2023

ShaunCorbs said:
Do you have down lights eg spot lights ?

Nope, nothing that would make the job any easier.

Here's what our boiler/kitchen layout looks like roughly. Boiler is inside what is presumably a specially manufactured cabinet (consisting of a side finishing panel, some parts of a base cabinet and a base cabinet door). Floor is solid concrete with self levelling screed laid over top (but only to the cabinet plinth locations).

Plus did I mention that everything not on show (95%) is in 15mm polypipe or for radiator drops in 10mm polypipe.

We are not even certain what type of joists have been used. I am guessing i-Joists but could be anything.

ShaunCorbs · May 1, 2023

I’m guessing the main fused spur for the heating is by the cylinder as well ?

Can you confirm what that grey wire does ?

magician2905 · May 2, 2023

ShaunCorbs said:
I’m guessing the main fused spur for the heating is by the cylinder as well ?

Can you confirm what that grey wire does ?

No the Main Fused Spur is located next to the boiler in the kitchen (on the outside wall).

By Grey Wire I am guessing your asking about the wire that currently is wired into the L on Switched Line 1? If so, honestly I have no idea as there are 5 sets of grey outer sheathed wires (2Core+E & 3Core+E) when they finally exit the wall in the airing cupboard and are wired into the wiring centre.

I don't have the kit to easily test for continuity plus i'm not Gas Safe Cert'd so technically shouldn't be popping front of boiler off and dropping wiring control centre in the boiler to gain access.

Putting those issues to one side I would have to jerry rig something (aka isolate, remove fuse, switch off MCB then run some wire from boiler to wiring centre location) to test for continuity to determine exactly which wire this is in the Wiring Centre.

But I think I get where your going with the question. If the grey wire exits into the wiring centre this could be repurposed as the Switched Line 2 as the L is simply a Live wire that could easily be replaced with another Live connection (or even just linked from the L to the right of it)

The system was almost certainly wired up like this originally (using Danfoss TPOneM (wired thermostat/programmer) and and TPOneB (wired thermostat). These were simply awful to use, even for me, and my elderly folks had no chance so were replaced with the Drayton Wiser Kit 3 by a sparky.

This is the current wiring centre attached to the Kingspan HW Cylinder along with the layout on the inside of the lid (when I mention Grey Sheathed Wires I am talking about Twin or 3 Core and Earth, some of the wires inside these also have grey sheaths)

magician2905 · May 2, 2023

Shaun & others,
Just wanted to say thanks for any and all assistance!!!
Paul

ShaunCorbs · May 2, 2023

Yes spot on need to have a look behind the boiler fused spur to see where it goes

And yes best to leave the cover on

Heat Only Boiler + S Plan+ + Weather Compensation Query

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