The Efficient Home Forum

Hi,

We currently have evohome setup throughout our home, we are having an extention and are considering getting underfloor heating and connecting to the evohome. The room is 6m x 4m will have two vellux sky lights and 5m bifold doors, i am wondering if we would need a radiator or two as well? Can anyone recommend a brand of underfloor heating to work with this and would it be water based or just electric?

Thanks
Mark

We recently had an extension measuring 5m x 7m with wet UFH being the sole form of heating. Electric UFH was quickly rules out due to running costs. We contemplated having a radiator or under cabinet space heater too thought it was unnecessary as the UFH was able to heat the room comfortably. The only thing to note is that UFH will do a great job of maintaining a steady temperature in a room but is not great if you want to heat a room quickly, e.g. if you get home cold and wet and want a boost in temperature for an hour.

The plumber installed a Wunda UFH kit for us with a new Worcester Bosch 4000 combi boiler. The central heating system is controlled via a 2 port valve with its own BDR91 which is programmed as a boiler relay. The UFH system (which only comprises one zone at present) is via another 2 port valve with its own BDR91 which is programmed as electric heating. To get the boiler to fire for the UFH I have wired the orange wire from the 2 port UFH valve to the boiler.

I also bought an opentherm bridge and Nefit OT to EMS adapter (which works for me) but have removed this from the setup as I can't have the UFH configured as electric heat whilst also getting Evohome to fire the boiler.

pujum wrote:The UFH system (which only comprises one zone at present) is via another 2 port valve with its own BDR91 which is programmed as electric heating. To get the boiler to fire for the UFH I have wired the orange wire from the 2 port UFH valve to the boiler.

I also bought an opentherm bridge and Nefit OT to EMS adapter (which works for me) but have removed this from the setup as I can't have the UFH configured as electric heat whilst also getting Evohome to fire the boiler.

I'm not entirely sure why you have configured your system this way unless your hydronic setup is not standard? evohome should be using a boiler relay or OpenTherm Bridge to call for the demand for all technologies bound to it. Adding as an 'electric zone' removes the demand capability from that particular zone and then adding another switched live back to the boiler from the zone valve, completely removes evohome from any decision making (TPI or OpenTherm control) and all of the energy savings that go with it?