Wet underfloor heating- setback or not?

[sjroberts1]

Hi
Currently in my house we use wet underfloor heating running off an oil boiler, each room is individually controlled and we do not use any setback, the heating is on all the time whenever the stat calls for it. This has always worked very well and have been pleased with it.

We are about to move into a house that again has wet underfloor heating but this time running off a ground source heat pump with a buffer tank and every room is controlled by a programmable stat. Having looked hard for info into using the setback or not I'm still undecided, does anybody use the setback feature or just leave it on a fixed temperature control all the time?

Be interesting to hear what people do and which is the most economical.

Cheers

Steve

 

[Agile]

The less heat you provide then the less cost to you.

I never understand why people who sleep ( that's most ) don't invest in a nice duvet and lower the heating overnight.

It also gets me more cuddles too!

Tony

 

[sjroberts1]

I love a blanket on the sofa lol, was just wondering if anybody had any experience or knowledge of heat pump and setback control.

Cheers

 

[JonG1]

With a GSHP it is important not to allow air temps to drop too far, because depending on the unit and design of the system, if it has to work too hard to recover it may recruit an onboard immersion to achieve the new set points.

We don't advocate more than a 2 degree air temp set back for a heat pump, most of our clients just have a single set point temp and some who have experimented with set backs have had higher running costs.

It is hugely design specific though in so far as the insulation levels of the house are concerned the outside ambient, the heat pump and its design and control parameters, the design and spacing of the UFH, floor coverings etc.

If you have some more info we may be able to be more accurate.

 

[sjroberts1]

Thanks Jon

Downstairs pipes sitting on 50mm celotex in 25mm screed pipe centres 100mm. Upstairs clipped to 25mm celotex again 25mm screed and 100mm centres. Floor coverings downstairs is 14mm engineered oak flooring and upstairs a thin carpet and underlay with tiled bathrooms. It's an old house with solid stone walls about 2 foot thick which has been externally insulated so insulation levels are quite good.

Forgot to say, there's no immersion for the heating side

 

[JonG1]

With those floor coverings and such a thin screed I would not set back at all, there is very little thermal mass to hold the heat and what there is will be restricted by the insulative wood and carpet.

 

[sjroberts1]

that's the way its running and that's the way its likely to stay then, cheers Jon