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Panasonic's new residential CO₂ air-to-water heat pump:coeff of performance=6.1

18 points by bookofjoe ago | 3 comments

anenefan [-]

Interesting but sadly not forward thinking enough for Australia least where a handful of months it would be beneficial to pipe cool water or cool a room as well. I have viewed [1] [2] (source) and don't see any additional options to redirect any cooled air or water.

There other thing is adoption of such units would be restricted to power grids with very stable power supplies, ie not more regional areas where induction motors are not dying every few years due to grid power failure mode - unless one has decided to bite the bullet and stabilise with solar / battery arrangement.

[1] https://plumbingconnection.com.au/panasonic-releases-co%E2%8...

[2] https://www.panasonic.com/au/corporate/news/articles/panason...

fy20 |root |parent |next [-]

The big thing here seems to be that it uses CO2 as a refrigerant. I had a Hitachi Yutaki air-to-water heat pump installed earlier this year, the model generation was first released in 2015, so it's kind of old tech now. It has a SOP of up to 5.25 depending on the configuration, and works down to -25c in heat pump mode.

I went with the R410A version, as the R32 version has hydraulic lines between the indoor and outdoor units, and I didn't want to risk them freezing during winter (where I live it's a little colder than Australia). I guess CO2 heat pumps are the same, and they just haven't got around to releasing the reversible version yet.

(I wouldn't recommend this model however, the software is pretty bad. It can't even calculate what SOP it is operating at. I wanted to get Panasonic, but my contractor insisted on a company that supplies Hitachi instead).

winstonwinston |root |parent |previous [-]

This model looks pretty good on paper based on what it claims: up to 6.1 COP and is able to reach water temp of 59C. If it is able to deliver that would be news. So far models popular around where I live are all up to ~5.1 COP and are actually very popular alternative to gas heating, obviously you can use air-to-water heat pump for cooling too.