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Defrost cycle question
Sorry if this is a daft question:
But after reading about defrost cycles I'm pretty sure I understand the basics of what is happening.
Instead of heat from the environment being used the increase the temp of the heating circuit, during the defrost cycle heat from the heating circuit is used to warm the environment (melt the ice off the radiator)
All the descriptions I've read use the word reverse, the heat pump works in reverse or the heat pump reverses.
Does the actual water pump pumping the water round the heating circuit reverse direction?
Or is the 'reverse' just referring to the heating 'mode' reversing (going from heating to cooling) rather than the water flow reversing.
I'm pretty sure its just talking about the mode but after lots of searching I could find nothing definitive on the water pump direction.
“Anything worth doing, is worth doing right.”
A valve in the heat pump causes the direction of the refrigerant to change. The water circuit carries on pumping as usual.
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.
@hughf Thanks for that.
Ah so they are talking about the refrigerant circuit direction reversing.
I knew it couldn't be the water circuit logically, I think it has been a rather long week 😆
“Anything worth doing, is worth doing right.”
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