Control Heat Pump With Wall Thermostat

[wwhitney]

It is better to vacuum the rest of the line before releasing the pressure into the system.
Humidity does no good in the system. At least do the piping during hot summer weather

I think that during cold weather the absolute humidity would be lower, and so you would end up with less water in your non-evacuated lines.

Cheers, Wayne

 

[arnis]

Correct. Usually people install heap pumps when it is about to get cold, aka autumn during massive rainstorm :lol:
But below freezing, even better.

 

[QueenBee]

I really hope no one is actually installing heat pumps without nitrogen pressure testing the lines and vacuuming them. I suspect what the poster was saying is they have a heat pump that is a single through wall unit, like a window AC unit.

It's very easy to buy the units and lines in the US. The hard part is finding someone willing to commission it. I finally found a semiretired HVAC tech from Craigslist who was willing to is it.

 

[arnis]

99% of small split systems are installed without pressure testing here.
But vacuuming the line is recommended for best performance.
It doesn't have to be expensive vacuuming. Old refrigerator's compressor
does excellent job with vacuum. Valves are integrated onto outside unit
which are prefilled with gas and oil (correct amount).
Copper lines must be cut and chamfered with small handheld tool.
It is DIY procedure except vacuum. Vacuum pump needs to be built,
some adapters and soldering. 2-3 hours to make that

BTW, great business opportunity.

 

[Graycenphil]

Mine is a genuine split system, not a through the window unit. It is designed specifically for self installation. The lines are sealed, and I believe, evacuated and precharged. I don't believe you could evacuate them if you wanted to - you would lose the seal.

The system has been fine for a year. I also installed a home central AC unit with a similar setup, and it has been working fine for 16 years, so I'm fairly comfortable with the concept.

 

[QueenBee]

Mine is a genuine split system, not a through the window unit. It is designed specifically for self installation. The lines are sealed, and I believe, evacuated and precharged. I don't believe you could evacuate them if you wanted to - you would lose the seal.

The system has been fine for a year. I also installed a home central AC unit with a similar setup, and it has been working fine for 16 years, so I'm fairly comfortable with the concept.

Strange, hadn't heard of such a thing. have a URL?

 

[Graycenphil]

http://growershouse.com/mrcool-diy-series-ductless-mini-split-heat-pump-system-16-seer-24-000-btu-with-wifi