What is incremental power needed to raise house temp a few degrees with Mitsubishi minisplits?
I have an all-electric house in MA heated exclusively with two MUZ-FH09NAH ( ductless minisplit with pan heater). This is my first heating season so I am still on a learning curve and am desirous to optimize my costs and comfort.
I was pleasantly surprised to find that the Mitsubishis generated heat even as the thermometer plummeted to minus 7.6 F a few weeks ago. We keep them set to 64 degrees indoor but want to know what incremental power consumption would be incurred if we raised temp to 66 or 68 degrees. In order to answer this, I tried to use the manufacturer documentation, linked at the following URL, specifically the table on page 14 and the graphs on page 16, screenshots will be attached.
https://www.manualslib.com/manual/908936/Mitsubishi-Electric-Muz-Fh09na.html
Reading the heating tables has been frustrating and counterintuitive so I hope for some GBA guidance. I am looking to optimize TPC (total power consumption in kwh).
1.查看第14页的表，看起来TPC的室内温度从65度提高到70度（tpc @ 65 of .62 of .62 vitus tpc @ 70 of .64）。这似乎是一个非常合理的增长。
2. It is counterintuitive (for me) to see that TPC *increases* as outdoor intake air temp increases. Shouldn’t the indoor heating TPC be *less* when the outdoor temp is 55 (TPC = .74) degrees than it is when the temp is 35 (TPC = .66)? I realize that the delta temp magnitude drives the heating engine, but my ears tell me that the duty cycle (ie when the outdoor unit is working hard) is more frequent at 35 than 55. Will my Spring heating bills actually be higher than my Winter ones?
3. My confusion is reinforced by what looks to me like an axis error for the graph of FH09NA, which shows the 65 degree interior temp has a *higher* TPC than 75 temp, while the opposite is shown for the FH09NAH graph. I think the typo is on the latter graph, no?
关于如何理解这些表的简短入门对我有帮助。
Thanks, everyone.
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Replies
肯尼思（Kenneth），三菱文档不会告诉您问题的答案。升高温度所需的能量是您特定房屋和热泵安装所特有的。我建议使用能量监控器测量它。这是我的最爱：https://stuff.iotawatt.com/
Increasing the indoor temperature will:
1.增加热负荷 - 所需的热量。如果您的室内/室外温度差异为7O，则一阶估计是，如果将室内温度提高，如果将室内温度提高，如果将其增加7度，则将增加10％。
2. Decrease the output of the heat pump, when it's running at maximum.
3.当热泵最大运行时，降低热泵的输入功率。
If the effects 2 and 3 where the same size, they cancel out and wouldn't affect the total energy consumption, and only effect 1 would matter. But the decrease in heat output is bigger than the decrease in power consumption. So those two make things a little worse as well.
The net result of 2 and 3 is rolled in to the COP. So if you look at the data for COP, and combine that with effect 1., you'd get a reasonable estimate.
今天早上在明尼苏达州国际瀑布（International Falls）和您的路上是负44 f。您可能有时间升级电动面板。让我们知道Minisplits在未来几天的表现，我对热泵技术的进步感到惊讶。
>我的春季供暖费实际上会比我的冬季高吗？
The total power consumption (TPC) they list is a maximum and should not be confused with the power consumption that you will pay for. Your spring bills will be lower - mostly because load is lower and partially because efficiency is higher.