UFH Best Practice for Zoning and Control

[umiq88]

Does anyone have a good design guide or insight on the best way to setup UFH and what the best controls are? 2 manifold system individual mixers fed from oil fired boiler with 100l buffer.

 

Ideally I would like to be able to set lower temperatures in the bedrooms and lower the setpoint at night. The only point would be to reduce costs.

 

Ideally would like each room zone and to be able to control thermostats centrally via a web browser or app.

 

Is there an off the shelf solution for this? Something similar to a Hive for conventional system.

 

 

 

 

[JohnMo]

UFH is extremely slow responding system anyway you look at it. Slow the flow rate down in areas you want cooler, by reducing the flow meter rate. 

 

I have reverted to trying to keep the floor at a constant temperature, waste of time doing set backs as it never gets to the temp you want when you want. Unless you have super thin screed and high flow temps.

 

A lot depends on how well insulated you are, and at what flow temps you need.

 

Not a fan of zones. But if instant you need thermostat with a low hysterisis, ideally 0.1, to stop over and undershoot, most smart (?) thermostats are not that good from the specs - ok for radiators not so good for UFH.

[Andehh]

We basically ramp heating up for octopus cosy periods, plus extra time for when it gets properly cold, then drop temps all other times.  Bedrooms slightly cooler then rest of house by room zones.

 

House varies by a couple of degrees over the course of the day, but it's warm!

[Conor]

New build or existing? Heatlosses will be a massive factor. In our new house, two zones, just on a dumb timer / room stat. No need for smart apps or multiple zones. Temperature through house is uniform.

 

The key thing for a boiler will be able to run in the optimum condensing temp range, and not short cycling. 

[umiq88]

New Build 150mm PIR in floor and 130mm PUR in wall. 

 

@Conor what setup would you recommend to prevent short cycling and keep return temps right?

 

@Andehh what thermostats/controller are you using.

 

 

[Andehh]

Heatmiser, it's a good one but we have over zoned it..... But nothing plaster and paint can't fix if it does prove to be an issue... Which for now it isn't!

[JohnMo]

Oil boiler, stick in a thermal store, draw UFH from that via pump and mixer. You can have as many or few zones as you wish.  But smart controls with UFH are a waste of money. So keep it simple.

 

Oil boiler happy with a thermal store, as it can run for as long as needed and will nit short cycle. But the thermal store needs to larger than UVC, also get one with a decent size DHW coil or heat exchanger, so you don't need to run the TS really hot.