1950s underfloor heating brought into reuse with air source heat pump

[BobTheBuilder65]

My mother moved into her three bed home in 1960 and it had underfloor heating in the living room. I remember we used it when I was growing up in the 70s but it hasn't been used for probably 30 years. Electric storage heaters were installed to take advantage of the old off-peak electric tariff that preceded economy-7 but now she's got new Sunflow electric heaters around the house that are costing a fortune to run on a standard tariff. The thermostat for the underfloor heating is still on the wall but I won't risk trying it without a safety test first!

With air source heat pumps now able to supply underfloor heating, would it be mad to try to connect this 62 year old system to an air source heat pump and get it working again? Would it even be more cost effective? There is a gas fire in the room as well so next winter we've currently recommended she uses this in preference as cheaper to run and maybe keep the Sunflows at a low base temperature.
Installing radiators for either a gas boiler or an air source heat pump won't happen as too much disruption to my mother of course so that's why I started to think about the old underfloor system!!

Thanks in advance

 

[James]

If it is a wet (piped water) underfloor heating system then a pressure test and a flow check will confirm if it is good to repurpose for heat pump.

 

[brianmoooore]

What wa.......
What James just posted above. Beat me to it!

 

[BobTheBuilder65]

If it is a wet (piped water) underfloor heating system then a pressure test and a flow check will confirm if it is good to repurpose for heat pump.

My guess is it's not water based as it would have been embedded in concrete. I'm trying to research 1960s UFH on tinternet to find out more about the technology but might have to go to a museum instead

 

[James]

Pipes can be installed in concrete you know?

if there are no pipes then the original question of can it be repurposed for use with a heat pump is No it can’t.

 

[SJD]

I have several customers in 1960's / 1970's properties that had UFH installed when built. Thy are all electrical, and mostly all failed with either open circuit heating elements, or appalling insulation resistance, or both. On top of that, they are installed in concrete slabs with usually no insulation below, so you end up warming the ground nicely for the worms.

Usually this UFH was installed because there was no gas available at the time, or they were flats and gas was frowned upon. Mostly they now use some combination of storage heaters and panel or similar heaters. In one case, they (recently) retrofitted wet / gas heated UFH on top of the old floor, which added about an inch to the floor level (bungalow, wet UHF added throughout), but they still waste heat into the ground as there is no insulation.