I thought switching to a heat pump would be a weekend project

I bought a ductless mini-split for my garage workshop in Portland last fall. Figuring out the electrical line, mounting the outdoor unit on a concrete pad, and running the refrigerant lines through the wall took me three full weekends. The hardest part was getting the vacuum pump to hold the right pressure on the lines for an hour before releasing the refrigerant. Has anyone else done a DIY install and run into this? What did you do to speed it up?

3 comments

3 Comments

campbell.andrew27d ago

Did you check the flare nuts on your service ports before you even started the vacuum? I had the same headache until I learned those factory nuts are often just hand tight. I take them off, clean the mating surfaces with a bit of refrigerant oil, and re-torque them with a wrench. It made a huge difference in getting a solid seal fast. That hour hold test can turn into a whole day of chasing tiny leaks if those ports are weeping from the start.

victor_carr2527d ago

Oh man, you just saved me a whole weekend of swearing at my gauges.

the_elliot8d ago

Honestly I think people stress way too much about that hour long vacuum hold. If your system is holding any vacuum at all after ten minutes, you are probably fine to just release the charge. The whole point is to get the moisture out, and a deep vacuum for a short time does that. I have done a couple installs where I only pulled vacuum for twenty minutes and they have worked perfectly for years.