Hi all,
I have a 2700 sq ft house over three floors, currently using 2 x 26KW 20 year old non condensing system (H + HW) boilers and 300L HW tank w zoned floors controlled by 3 nests.
Getting massive Gas Bills, have insulated as much as possible and now replacing both boilers for a Viessman 100W as don’t think the house is airtight enough for a heat pump.
I want to use OpenTherm but can’t do three Zones apparently.
I’m considering opening up the house to 1 large zone and using weather compensation. Happy enough to rip out the Nests or go for a different boiler option.
Can anyone give me a steer on how best to design this? The plumber is proposing leaving the current nest setup but we hate the hot / cold, on / off system we currently have.
Thanks……