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Starting our heat pump journey in 4 bedroom house (possibly)
@njt Same here. We have 6.9 solar and a 6.5 kWh Growatt battery. Since, I switched to cosy after the heat pump install, we fill up the battery thrice a day and that runs the heat pump and the base demand without importing from the grid during the peak hours. I wonder whether getting another 6.5 kWh battery would prolong the life of the battery due to fewer cycles. One for spreadsheet modelling!
16 * 435 watts PV
13 kWh Growatt battery
1 EV - Mercedes EQB
6 kW Aira Heat Pump
Bosch Induction Hob
Pod Point Solo 3 charger
@callum_62 That does sound excessive. We are in a slightly older new build, around 12 years old, 4 beds (and a study) and three reception rooms including a 30 sqm open plan living dining kitchen. We paid a lot less (around 40% less) for a 6 kW heat pump with a 200 L tank and six rad changes. But also reused three rads from downstairs rooms for the upstairs rooms.
16 * 435 watts PV
13 kWh Growatt battery
1 EV - Mercedes EQB
6 kW Aira Heat Pump
Bosch Induction Hob
Pod Point Solo 3 charger
Posted by: @callum_62@editor Hi - sure
Aira 6kw 250l tank - 8 rads changes - £17k
Arotherm 7kw 200l tank 8 rads - £19k
Vaillant 5kw 200l tank 6 rads - just under £15k
All include a variety of radiator upgrades - generally changing any K1 to K2 rads
My house is bog standard 4 bed detached new build- no weird or complex pipe runs either from what I could tell and they advised - no pipework upgrades were factored. We already have a system boiler so new tank would go where current tank is
Basic heatloss around 5.2kw
I'm not saying what I've been quoted is overpriced as they come in sort of around the same but I'd have thought our house would have been on the cheaper end of the scale - and yet some are more than the grant and the max interest free loan combined!
I got several quotes like this for a (on the face of it) similar season.
I also got two quotes of 5K + BUS grant, from the installers I anyway trusted most. Add a couple of K for the fact that, by the time I got sensible quotes, half of the rad upgrades had been done and so say 7K + BUS grant.
My advice - shop around!
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
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