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Last seen: Aug 1, 2026
Yes the unit always performs its defrost cycle, every 40 minutes, and the ice always clears. With the evaporator at -23C when it starts its defrost c...
Thank you. The pipe work is now insulated. Finding a heating eng that knows Hitachi units in this area is difficult. However, as you said a quali...
It sounds like its ice build up and does not sound good. Looking at the algorithm it looks like I am set to the Jo-0 setting, but I don't fully under...
I suspect it's ice build up. Just does not sound right.
JamesPa Could I ask for your interpretation of the defrost algorithm for the heat pump? I am seeing a defrost at around an outside starting tempera...
I did manage to find the spec on the HP and that it can only modulate down to 2.1Kw. And very few other HP on the market get much lower. I have bou...
James Thank you for your help. I will work over the next week to try and produce the data requested. This is still new to me so still a step learn...
James I understand your point about turning the heating off and on or up and down and the resulting effect. Today the one room thermostat controll...
Re the chart that I posted. Could someone comment as to why the subsequent defrost cycles do not perform as per the the first at 3.30pm?
Just to add. As the system is not that common I have been unable to find anyone local who knows anything about the system or what I can do to fix it....
Re the chart. I should of added more info. The first part of the chart shows the performance during the day with one defrost occurring at 3:40pm....
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