Underfloor Heating: Best Practices?

hilljd00

Hello :beer:

I have had underfloor heating since 2009. But no one seems convinced of the best method on how to heat a home using this system.

What do you do and why?
- I'd be interested to know what temperature/hours you have set.

Thank you.

matelodave

What sort of underfloor heating. Hot water or electric.

Is it embedded in concrete. If it's electric are you on an E7/E10 or complex metering tariff.

If it's hot water, what feeds it, gas boiler, oil boiler. what's your flow temperature?

How is it controlled - timer, programmer, thermostat etc. If hot water do you have manifolds to distribute the water to differnt areas?

I've got an overlay hot water u/f system fed by an air source heat pump which runs virtually continuously at this time of the year. The flow temperature varies between 30- 40 degrees, depending on the outside temperature and the house is split into separate zones, each controlled by a programmable thermostat which varies the required temperature at different times of the day.

We do not shut the heating off but turn it down by 2-3 degrees overnight or in rooms that aren't in use during the day (bedrooms & bathroom) otherwise the place can get too cold and it takes a long time to reheat.

As it's an overlay system, it's a bit more responsive than a system where the pipes are actually embedded in the floor screed but still quite slow to react.

Cardew

Compared to conventional central heating, UFH is generally used at low heat for a long period; which is why it is so suited for use with a heat pump.

beborn

I wrote a bit about this in another post, but roughly my setup is:

District central heating and wet underfloor divided in 3 zones each with their own thermostat.
The pipes are laid out in concrete and the pump mix temperature is set to 45°. Pump is running at level 2 velocity. There are 3 levels.

I usually have it set to turn on the living room which is where I do most of my life at 16:00 and turn off at 22:00 weekdays. Weekends turn on at 7am turn off at 22:00. Target temperature at 21°, the thermostat will call for heat when dropping half degree from the target (so at 20.5° in this case).

It usually takes to heat the living room from ~20.5° to 21°, about 3 hours.

The heat inertia means after reaching the target temperature of 21°, it still will rise till ~21.6°, meaning in the same day it will not need to call for heat again.

But the heat loses when cold and not sunny outside are about 1° after 24h which means almost for sure the next day the heating will turn on again to get back to the target 21° unless sunny and not too cold outside, then it might "jump" a day although that means the living room could drop under 20° and then the next day it will take longer to reach the target.

Bedroom don't usually need to heat as I like it a bit colder and it is usually around 19°-20° at night. Very rarely under 19°.

I'm quite new to underfloor heating being this my first winter with it and not sure if I'm doing it wrong. Any recommendations are appreciated.