Thread: My new project
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Old 04-21-13, 06:57 AM   #93
Apprentice EcoRenovator
Join Date: Feb 2010
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There is a heat pump technology called 'enhanced vapour injection' which appears to alter the capacity (and perhaps efficiency) curve across various outdoor air temperatures.

See page 3 in this doc:

Or see figure 5 in this doc: It shows better COP at lower temps. Heat pumps with such technology would perform -a little- better than that spreadsheet's adjusted HSPF values would indicate, in colder regions. Figure 4a confused me for a moment!

Last edited by mrd; 04-21-13 at 07:03 AM..
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