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Replace your heat pump? People installing new heat pumps are going to see much higher efficiency.

50,000 BTU = 5.27528 * 10 ^ 7 J = 14.6 kWh / 6.6 kWh = COP of 2.2 at 50f which is absolutely terrible. Modern heat pumps should have a COP around 4 at those temperatures and 3 near freezing.

Also, “Subtracting 10%” would mean your grid losses are 17%. “annual electricity transmission and distribution (T&D) losses averaged about 5% of the electricity transmitted and distributed in the United States in 2018 through 2022.” So, (70% * (1 - 5%)) = 66.5%, but resistive losses are reduced in the cold. https://www.eia.gov/tools/faqs/faq.php?id=105&t=3

4 * 0.665 = 2.66x though obviously what matters here is the annual average COP. (3 * 0.665) = 1.995 aka 2.




So I have to spend 10k on a new heater every 10 years just to keep up


I was assuming something was broken or had made a very poor choice of device. He clarified he was reading the wrong column, so it’s not quite as bad.

The technology isn’t advancing fast enough to make upgrading every 10 years necessary. You could buy units in 2000 with a significantly higher COP than he was implying.


Its brand new!

Also, should have been 60,000 BTU - its a 15 SEER unit.


2.7 COP is a a noticeable improvement but still terrible at those temperatures. Are you sure it’s 6.6 kW?

PS: 2.7 COP * 0.665 = 180% efficiency which still crushes the 80% heat pump in your example but these numbers should be much higher.


15 SEER is garbage American manufacturers dump on people. Asian manufacturers are making 25-35 SEER systems.


15 SEER relates to cooling efficiency, what is its HSPF rating?




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