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Heat pump domestic hot water.
Quiet on here so thought I would jump on. What is your consumption when heating domestic water, mine is 5.2kw at the min. 16kw pump.
@johnmo I guess it depends on how much water I use whilst I’m splashing about like a bear. But it fair heats it up quick. This year will be the year to test it all out properly.
@johnmo yup exactly, you are correct, no idea how that could be done and I was just wanting a ball park figure. When the heat pump kicks in after a shower it registers 5.2kwh on my app, and was curious what other folks did. Not how much or how long it ran just what it uses as it’s running in anger. Hope that makes sense now.
Posted by: @david999Quiet on here so thought I would jump on. What is your consumption when heating domestic water, mine is 5.2kw at the min. 16kw pump.
We’ve got a 16kW unit as well, and we’re seeing similar results to yours at around 5.5kWh for hot water at the moment.
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Posted by: @editorPosted by: @david999Quiet on here so thought I would jump on. What is your consumption when heating domestic water, mine is 5.2kw at the min. 16kw pump.
We’ve got a 16kW unit as well, and we’re seeing similar results to yours at around 5.5kWh for hot water at the moment.
Seen similar mentioned for big Vaillant units. I would consider doing a comparison trial just heating with the immersion and compare. Also double check against the electric meter, to check what you see is real.
I thought it needed the immerser to heat the water up to 55c but it seems to be doing it all through the heat pump, which surprised me. I have my flow set at 35c and see how it fairs through winter, I’m happy with a home temp of 19-20 so might lower the flow temp a bit yet.
Posted by: @david999thought it needed the immerser to heat the water up to 55c but it seems to be doing it all through the heat pump,
Possibly why you use so much electric, likely the heat pump is starting the immersion as it's not capable of getting there on its own. Turn the demand temperature down for DHW to 50 or below.
Looks like you need to step back a little to get the system set up correctly - otherwise you may need deep pockets to lay for the bills.
so not running weather compensation?Posted by: @david999have my flow set at 35c
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