Loxone Heating System Schematic

[JTD Group 123]

Hi All, 

Could anyone with heating experience take a look at my schematic for a heating system we have installed in a loxone smart home - Due to 2nd fix in the next few weeks. As you will see the heating system compromises of :

x3 UFH Zone 

x1 Towel Radiator Zone 

x1 Hot Water 

So total of five 2 port valves, one cylinder stat and one hot water heating programmer. 

Note I haven't included the CPC on the schematic due to limited room 

From the outset at present, looking for clarification the wiring is in the correct formation as this is our first loxone incorporated UFH system. Touch Switches, actuators and heating schedules all to be set in config

May thanks 

[David Wallis]

No expert, but at a glance why the HW programmer and why not use a relay to drive that? 

No system pump as well as UFH pumps?

External Temp Sensor?

UFH Flow / Return Temp Sensors?

Room Temp Sensors?

:)

David

[JTD Group 123]

Thanks David - See my comments below

No expert, but at a glance why the HW programmer and why not use a relay to drive that?

- We could do, presumably this will give operation of hot water programming from a tablet or similar / hot water schedule through Loxone?

No system pump as well as UFH pumps?

- Integral to boiler / boiler pump

External Temp Sensor?

- No external Temp sensors being installed, we could offer this as a optional extra

UFH Flow / Return Temp Sensors?

Can the IRC’s regulate this temp?

Room Temp Sensors

IRC’s in all rooms - I’ve only shown one on the schematic for illustration purposes

Thanks

[Andy Wain]

Looking

My only comment would be that the manifold pumps would normally be switched by the motorized valves to. However to do this without all the pumps always coming on you would need to use a confection unit.

Tbh I've been on too many jobs where they have tried to do what you are doing and the have been all sorts of problems because they didn't use one of these.https://www.heatmiser.com/en/central-wiring-centres/

They mean that everything turns on in the right order, there are no feedback loops and it all works as it should

Btw companies like heatmiser have a free design service (country dependant) and will tell you exactly how much pipe you need etc

[Kevp]

1. As David said why are you using a a hot water programmer, it sort of defeats the purpose of having a Loxone system if you're not going to let it control as much as possible. Plus the Loxone system is far smarter and it can be programmed to not heat the water if people are on holiday etc.

2. One for future projects, If you have a manifold that is fully populated with the Loxone actuators then when you think about it the zone valve for that manifold is rendered pointless and might as well not be there. it certainly simplifies wiring when all you need to do is send a signal to the manifold pump and the boiler.

A zone valve for the hot water is necessary as that's the only form of control you have.

I'm on two large projects now with GSHP systems and 4-5 manifolds each and not a zone valve in site.

[RSinn]

Are you in the UK with an invented cylinder? If so make sure you check the G3 regs for the cylinder. you have to make sure the over-temp sensor can switch it's 2-port valve off so more hot water from the boiler doesn't enter the coil. It's a safety feature.

Also I think you are supposed to have the 2-port valves control the boiler firing i.e. only when there is somewhere for the heat to go like a manifold or cylinder will the boiler fire. If you find the Honeywell s-plan schematic it should be clear. Called Boiler interlock. Loxone relay open 2-port, when open its microswitch allows 230v to the boiler switched live and manifold pump.

[Duncan]

building regs doesnt require a 2 port valve to control the boiler, it just requires a boiler interlock to ensure the boiler isnt firing when there is no demand - this can be electronic using any smart system