Heating setup

[Scotsman1000]

Hi, I have a heatpump and underfloor heating in my home. It is currently setup as per the attached diagram.

The heat pump acts independently of Loxone currently, switching on and off depending on whether the buffer or hot water tank is calling for heat.

Loxone is currently setup to use the intelligent room controller v1. If the thermostat drops below the setpoint it turns on the manifold valve, and if at least one manifold is on the circulation pump comes on.

Is the the most efficient setup? Do I need any more sensors? I have tried to use the intelligent room controller v2, but it seems to need a direct connection to my boiler which I don't have. I'm finding the ios app user interface a little clumsy for v1. 

[Amit Shah]

Thanks for this post. I also have recently installed a Daikin Low Temperature Altherma Heat Pump. The heat engineer has configured the heat pump to run on a leaving water temperature model using a weather adjusted curve. It is therefore continuously on and running independently of any loxone config.

I have underfloor heating on 3 floors with a manifold per floor. I have wired the actuators, manifold pumps and zone valves to loxone relays. I also have wired a zero volt call for heat between the heat pump and a loxone low voltage relay. My idea was to control the heating logic via loxone however as a heat pump works differently to a gas boiler, I feel the above set up will be cycling the heat pump on and off when the temperature in rooms hits a set target say of 21 degrees, and this would not be the most efficient way to run the heat pump.

The heating engineer has therefore said I should leave the heat pump controls seperate to loxone and just manually turn on/off actuators and zone valves especially for the 2 upper floors. I do not think this is best way to manage all of this or most efficient. It is almost as if you are ignoring the temperature readings from each room's Touch Switch and you are also assuming the target level of the leaving water temperature of the heat pump will give you 21 degree's heat in your house.

Using a typical call for heat as and when 30% demand is meet in your house signalled by the average readings of the temperature sensors from all light switches will result in cycling the heat pump and will not be most efficient.

I have seen on loxone they recommend connecting the heat pump using a modbus extension. Please see the link below for the loxone daikin modbus library module.

https://library.loxone.com/detail/daikin-heating-cooling-1465/overview

This gives access to flow temperature's which seems to be of more importance than turning the heat pump on and off like you would a traditional boiler.

I think by using the loxone modbus extension and dakin home hub you should be able to control the flow temperature, zone valves, manifold pumps and actuators to get a much more efficient heating system? How does the loxone config look like for such a set up and would you recommend? Do you then have a call for heat and is that logic to turn on/off the heat pump or to switch between normal heating and a lower temperature set back flow temperature? Or is it better to leave the heat pump using leaving water temperature model and then as rooms need heating to open & close acutators/zone values/manifold pumps?

I look forward to any help on this.

Thanks,

Amit

[Simon Still]

I posted quite a few times about my own set up on here. (search for weather compensation).  

Having had heating that runs separately from Loxone, using weather compensation and no internal thermostats at all I can confirm it can work really well. The first winter might need a little tweaking of the heat curve but that's all.   

With underfloor heating running at a very low temperature the system effectively becomes self regulating. 

[Scotsman1000]

I played around with Loxone config last night and here's a version 2. Now, instead of the previous the underfloor heating circulation pump is controlled by a climate control block. Currently the circulation pump switches on when theres an average of 30% valve opening (switch on threshold). Cycling of the circulation pump isn't really a huge issue so I think I might adjust that lower to say 10%.

Seems to be working OK so far. I do think I could improve the efficiency though with more Loxone sensors and relays on the buffer tanks and heat pump. What I have noticed is that there's no way to monitor or control the buffer tanks and heat pump so I'm using energy to keep those hot unless I manually switch off at the heat pump. Ideally it would be good to control the heat pump too so that I could put the system in deep sleep if I was away over the summer for instance.

Heatmpump is a warmflow GS16.

Amit, does your heatpump have a buffer tank? Looks like your question is similar to mine: have loxone control just the valve actuators and the underfloor heating pumps, and leave the heatpump to run independently.

[Rug Head]

Hi Simon , please can you help me post questions, finding this forum impossible to navigate.

Have had loads of issues with Loxone and would love to ask the community.

Cheers fella 

Rug

On 22 Apr 2024, at 09:32, Simon Still <simon...@gmail.com> wrote:

I posted quite a few times about my own set up on here. (search for weather compensation).  

--
You received this message because you are subscribed to the Google Groups "Loxone English" group.
To unsubscribe from this group and stop receiving emails from it, send an email to loxone-englis...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/loxone-english/1823b24f-61ac-4961-909a-55745b1310a5n%40googlegroups.com.

[g...@camleyphotographic.com]

YES!

 

This is exactly how it should work!

 

If you r radiators are large enough, by which I mean HUGE, then they can operate like this too.

 

G

--

[Amit Shah]

I do not have a buffer tank even though it was included in the initial quotation. I am going to speak to the company who installed it and see if that can add. I have a distribution head which they tell me can act like a buffer tank but I am not so sure. The company that installed the system said I had enough volume of water within that head that I would not need a buffer tank.

Yes exactly the same question, where Loxone just controls the valve actuators and underfloor heating pumps and zone valves, and leave the heatpump to do its own thing.

I do however have a zero volt contact to turn the heat pump on and off from loxone, but think I need to be smart with the config side to put some logic in as to when to turn it off and when to turn it on. Any ideas on what logic to use for this?

Also when engineers refer to cycling a heat pump does turning it on or off every say 3 to 4 hours count?

@ Simon thanks for your posts. I am glad you have experience of the system self regulating. The issue I have was my system seems to be consuming 5 KW per hour continuosly to heat the whole house ( I have an 14KW Daikin Altherma Low Temp unit). Even though the leaving water temperature was hitting saying 36 degrees based of weather compensation curve, still the unit was consuming a lot of power and the house was super warm around 23 to 24 degrees across all rooms. Any ideas?

I since then lowered the heating curve by 4 degrees to reduce power consumed and lower overall temperatures. Now using about 2 KW per hour, but again not stop with no break. Thinking to schedule a set back temp during night hours from 11pm to 5am?  let me know your thoughts?

I have been using Heat Geeks on youtube who have some great stuff https://www.youtube.com/watch?v=SfgTOcclbCY

[Simon Still]

The objective with your Weather compensated heat curve is to balance the heat you're putting into the house with the heat it's losing.  If the house is too warm then your curve is too high so lowering it by 4C seems like the right move.  You will probably also need to tweak the slope of the curve as well.  easiest to do if you pick a regular point - is the indoor temp correct when it's 0C outside and 10C outside.  

If you've got a lot of thermal mass in the house (which you usually have with concrete slabs/underfloor heating) the impact of changes may take a couple of days to show. 

Just checking mine, today is 8C outside and my flow temperature is 23C.  

I have mine on setback from 2200-0430 (remember that high mass UFH is very slow to react) and my setback temp is 15C.

The UFH switches off (ie the pumps stop running) when it's above 13C outside (and that must adjust based on the setback temp as well - they do run at night if it's really cold out) 

Mine is controlled solely by the Viessmann controller - no link to Loxone.  I didn't see the point in recreating the programming of the Viessmann controller which might have some smart stuff in the algorithm that I don't know about.  Given that it is 'automated'  - because it turns off the pumps based on external temp theres not even a case of turning heating off for the summer.  The only time I touch it (via the Viessmann app) is to turn on 'holiday mode' setback if we're away for more than a week in winter. 

[g...@camleyphotographic.com]

And looking at your setup again…. Where are the radiators for your house? The ground loop?

 

You have a second circulator and buffer tank for your underfloor?

 

What temp do you run your heatpump? Ours is between 30c and 37c. I am just flummoxed by the purpose of your buffer tank and a second circulator. I thought the idea of underfloor heating and an ASHP was that you did not need mixers and additional pumps!

 

Anyway… I am not sure that is the question you were asking. Sorry.

 

G

 

 

From: g...@camleyphotographic.com <g...@camleyphotographic.com>
Sent: 20 April 2024 19:54
To: 'Scotsman1000' <1314ban...@gmail.com>; 'Loxone English' <loxone-...@googlegroups.com>
Subject: RE: Heating setup

 

A buffer tank with a heat pump. Heatgeek has a really interesting blog/video about these and what problems they can cause.

 

I control my ASHP via Modbus TCP. I bought a MOXA modbus tcp adapter to do this, plus some of the relays inside the MS to turn on/off circulators and valves.

 

The flow temp is controlled via  Heating Curve block. It does a good job. The ASHP comes on when two rooms demand heat, which is most of the time. There are only a few rooms, such as our bedroom, where we actually turn of the radiator as we never want it above 18.0C.

 

Our ASHP essentially runs 24x7 and it is the flow temp that is modulated to control the output, rather than turning the system on/off.

 

G

 

 

From: loxone-...@googlegroups.com <loxone-...@googlegroups.com> On Behalf Of Scotsman1000

Sent: 20 April 2024 14:56
To: Loxone English <loxone-...@googlegroups.com>

Subject: Heating setup

--

You received this message because you are subscribed to the Google Groups "Loxone English" group.
To unsubscribe from this group and stop receiving emails from it, send an email to loxone-englis...@googlegroups.com.

To view this discussion on the web visit https://groups.google.com/d/msgid/loxone-english/2def6ff6-ef4c-474e-90dd-dfb5ea8eef3cn%40googlegroups.com.

[g...@camleyphotographic.com]

A buffer tank with a heat pump. Heatgeek has a really interesting blog/video about these and what problems they can cause.

 

I control my ASHP via Modbus TCP. I bought a MOXA modbus tcp adapter to do this, plus some of the relays inside the MS to turn on/off circulators and valves.

 

The flow temp is controlled via  Heating Curve block. It does a good job. The ASHP comes on when two rooms demand heat, which is most of the time. There are only a few rooms, such as our bedroom, where we actually turn of the radiator as we never want it above 18.0C.

 

Our ASHP essentially runs 24x7 and it is the flow temp that is modulated to control the output, rather than turning the system on/off.

 

G

 

 

From: loxone-...@googlegroups.com <loxone-...@googlegroups.com> On Behalf Of Scotsman1000
Sent: 20 April 2024 14:56
To: Loxone English <loxone-...@googlegroups.com>
Subject: Heating setup

 

Hi, I have a heatpump and underfloor heating in my home. It is currently setup as per the attached diagram.

--

[g...@camleyphotographic.com]

Yup. Pretty exactly as you say…. leave it running 24x7 and modulate the temperature up and down by adjusting the flow temp.

 

I consider that turning of rooms is not because they are ‘at temp’ but actually that I want to direct the heat to the cooler parts of the house, or that I will override a controller and have a radiator continually on. For example, I have the office radiator on whenever the light is on because I like to warm my feet on it.  

 

Even if a room is ‘at temp’, then you should be lowering the heat in to keep it at that temperature, rather than cutting the heat off.

 

I assume you are familiar with PI heating controllers? That is what they are trying to achieve.

 

G

 

 

From: loxone-...@googlegroups.com <loxone-...@googlegroups.com> On Behalf Of Amit Shah

Sent: 21 April 2024 11:49
To: Loxone English <loxone-...@googlegroups.com>

Subject: Re: Heating setup

--

You received this message because you are subscribed to the Google Groups "Loxone English" group.
To unsubscribe from this group and stop receiving emails from it, send an email to loxone-englis...@googlegroups.com.

To view this discussion on the web visit https://groups.google.com/d/msgid/loxone-english/913f0ab3-8d44-4484-ba79-ef844595c0ban%40googlegroups.com.

[Simon Still]

On Wednesday 24 April 2024 at 10:18:36 UTC+1 g...@camleyphotographic.com wrote:

Even if a room is ‘at temp’, then you should be lowering the heat in to keep it at that temperature, rather than cutting the heat off.

Logically your curve should reach a point where (at a certain outdoor temperature) where flow temperature = floor temperature = target room temperature.  I've got a 'low loss header;' on my boiler, but presumably a buffer tank would serve the same purpose.  So the pumps can circulate water, but the flow and return are the same and the heat source isn't needing to add any heat.  that's the point at which you'd then switch off the heat source.

For me it's at 13C external.  8C outside today and heating system seems to be running at 22.5C