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Last seen: Sep 5, 2026
@travellingwave Ah yes, that would explain it.
@travellingwave A straight line like that in recorded data could be from a sensor problem, maybe OAT? Yes, the other points are suggesting 8-8.5kW ...
@travellingwave You don't need to record IAT to use the tool, if your IAT is usually 20C then as the tool defaults to 20C you shouldn't need to cha...
Hi @travellingwave If your system is on heatpumpmonitor.org then a chart similar to what @cathoderay is suggesting is already available. If you go ...
True there is a variation but importantly it's understandable. The ~560W value occurs before a defrost at 5C and so the ~560W is at the colder end of ...
@cathoderay The input power is largely determined by the compressor speed (it's by far the largest component) and that is set by the controller alg...
Or part of a cycle like a defrost or ramp up. Being able to set an arbitrary interval gives the greatest flexibility and doesn't preclude the use of h...
Hi @cathoderay This is a reply to two of your posts together. It's not a room stat per se but acting as one at the moment and its use...
Hi @sunandair I've posted charts showing the input power ramping up to the same 1-1.5kW in both (defrost and non-defrost) cases. Your image doesn't...
Hi @sunandair The analysis I previously posted was 90+ minutes long and not just 11 minutes. All of the electrical energy passing into the system go...
Hi @cathoderay If it helps any here's this period with recorded numbers: The off period is 1h22m and the on period is 2h44m, the system's steady ...
No worries! The WC curve is setup for our usual 20-21C IAT so that's what the heat pump is trying to achieve, but the "thermostat" is set lower and so...
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