The Homemade Heat Pump Manifesto

[Vlad]

Add my 2 Window A/C's with Cap tubes, and a 7KW reverse cycle ducted heat pump that originally had a fixed piston orifice and now has an EEV.

Originally Posted by BradC

The properties of R290 are so compatible with those of R22 that it's almost always a direct swap. Certainly charging critically charged systems can be a bit fussy, and yes superheat is important, but it's by no means impossible for the DIY hacker.

The problem with R290 is nobody(I mean big guys) want to promote it because it puts "environmental" BS in danger. Also it is so cheap, then they can't justify 10-20$ per lb price.

For DIY it is almost perfect solution, but with limitations. Like for indoor use legal charge in Canada must be less then 350 gram. In the US a have no idea.