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Posted by: @gshpwoes@kev-m the v hot water isnt all the time - was just when we had the cold snap - the hot water out the tap was really hot, despite the fact the rads were barely warm. but sometimes its not hot enough... ug. we do have a an immersion that was on the first week we moved in, and our bills were astronomical(even back with low kwh prices!) so i know it is definitely not on now as we switched it off. House is approx 300m2, so it is large, but i know people with much larger houses using a lot less kwh than us...
I would look for a 3-way diverter valve or two 2-way valves that divert the warm water from the heat pump to the central heating or DHW cylinder. It is possible one of the valve/s is sticking intermittently.
Please provide some photo's of your system.
Posted by: @gshpwoes@hughf we are purely electric no gas. our kwh per year was approx 20,000kwh but last year was just over 16,00kwh...
if we assume 18000kWh, that’s a 3kW immersion heater, on for 24hrs a day, for 250 days…. Are you sure you aren’t running on the backup heater in the buffer tank?
Off grid on the isle of purbeck
2.4kW solar, 15kWh Seplos Mason, Outback power systems 3kW inverter/charger, solid fuel heating with air/air for shoulder months, 10 acres of heathland/woods.
My wife’s house: 1946 3 bed end of terrace in Somerset, ASHP with rads + UFH, triple glazed, retrofit IWI in troublesome rooms, small rear extension.
thank you for all your replies and sorry im so clueless - im embarrassed i know so little after so much time!
@gshpwoes, there is absolutely nothing to be embarrassed about. These systems should just work, and for the geeks these systems allow us to geek out further, but it’s frustrating when they’re inherently broken. If you continue to struggle and would like a pro like @heacol to come out and investigate, I can connect you.
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Posted by: @gshpwoes@derek-m what photos would be helpful - i can take them tomorrow.
Wide view of the different parts of the system, then close-ups of individual items of equipment, along with screen displays from your controller showing anything of importance.
Basically the more information the better.
Locate your diverter valves or valves and see if you can check operation by initiating DHW heating then back to central heating. Check the temperature of the pipework around the valves and buffer tank or low loss header.
6kW immersion in the bottom of the hot water tank won’t be helping things….
Off grid on the isle of purbeck
2.4kW solar, 15kWh Seplos Mason, Outback power systems 3kW inverter/charger, solid fuel heating with air/air for shoulder months, 10 acres of heathland/woods.
My wife’s house: 1946 3 bed end of terrace in Somerset, ASHP with rads + UFH, triple glazed, retrofit IWI in troublesome rooms, small rear extension.
Why are you running your rads at 46 degrees in this weather? That seems excessive.
Off grid on the isle of purbeck
2.4kW solar, 15kWh Seplos Mason, Outback power systems 3kW inverter/charger, solid fuel heating with air/air for shoulder months, 10 acres of heathland/woods.
My wife’s house: 1946 3 bed end of terrace in Somerset, ASHP with rads + UFH, triple glazed, retrofit IWI in troublesome rooms, small rear extension.
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