The old woodburner never worked well, was not controllable, and was installed badly. The room was used as an office but only 3 days a week so instant heat was preferred, MrsF would get focussed on work and forget to add wood, etc. We removed it as part of the refurb as the hearth has been laid on top of the carpet, and plaster reinstatement behind was poor, and at the last service the flue was discovered to have been installed in 2 pieces and there was a gap in the join.
Religning the chimney was required, quoted at £1500. The air to air unit was £1100. A modern stove was also another £2k or so, so depite having about 5 tonne of wood stacked up, we cut off the flue and bricked up the hole, vented the chimney, at the bottom, and gained a lot of floor space.
Previously we had been using the main lounge, 18 x 12 feet, 3 external cavity walls, one window and 2 patio doors (no, we don't know why either), and running a 'living flame' gas fire for evening heat rather than heat the whole house. on 'low' this seemed to use about 4.4kW per hour, so costs about 30p/h or £1.50/evening This gradually crept the room from 15C or so up to 17 or sometimes even 18C during the evening when the blankets could come off our knees.
As part of the building works the old lounge is being knocked though, so some shuffling and a storage unit and MrsF's office is the new lounge. 12 x 15 feet, 2 solid external walls but with 35mm insulated plasterboard on the external walls, and 3 windows. And the air to air unit, like this inside...
https://mhi-hvac.co.uk/our-products/res ... t-systems/
There has been a bit of getting it comfortable, adjusting flow angles, set temp, operating mode, fan speed to warm the room but avoid sudden draughts, etc, however we now leave it set to 23C in Eco mode, which according to the datalogger holds 18C at coffee table height with minimal fan speed and virtually no noise.
Energy consumption calcs are tricky, as we have solar and battery, so the smart meter readings are only of use once the battery is flat, by which time we're turning it off and going to bed. I did leave it on overnight by mistake one night, but I basically compared our daily import of electricity for the periods before we moved over and afterwards, and added on any solar generation. The result has been an increase of electricity use of circa 3.3kWh/day, so about £1/day extra.
However, there is more to this. The room is warmer, getting swiftly to 18C and somtimes we turn it down as it gets to 19C. We also run it for most of the day now, as with half the house full of dust and rubble we've hunkered down at this end. I put it on at 1pm when we came in for lunch and the coffee table is saying 18.5C some 40 min later. Combined with looking at the 30 min evening data from after the battery goes flat, it seems we use about 150-200Whrs more than our background 160Whr/30 min period in the small hours, so the actual running use of the system seems to be about 350W, so about 10p/hour - a third of the cost of running the gas fire.
OK, so the room is a bit smaller, better insulated, but both have thick curtains, the same solid floor, and it is more comfortable, but if you're one of the hundreds of people who are getting a nice modern trendy woodburner installed each week, it might be worth thinking about one of these instead. Once the new room at the pther end of the house is done we will be gettting one in there (planning permission required for a second external unit) instead of the other options we considered (woodburner, gas fired 'woodburner' style heater, etc).
And in the summer they cool the house using energy from the solar panels
Paul
