The top floor of my house doesn't have air conditioning, so I'm considering putting in a mini-split. I have two other mini-splits in the house, but this room at the top that doesn't have one is the only room that really needs it, since it gets the majority of the heat gain. Is this something I could do myself? I watched a few Youtube videos, and it doesn't look too bad. Basically:
- Install a bracket for the indoor unit
- Cut a hole in the wall, install indoor unit
- Run refrigerant lines, drain, electrical from indoor to outdoor unit
- Install a circuit for it, and a disconnect box
- Cut and flare refrigerant lines, torque connections
- Purge lines with nitrogen and/or vacuum pump (is nitrogen necessary) and check for leaks
- Open valves to release pre-charged refrigerant into lines
So I'd need to but a vacuum pump, refrigerant manifold, a tubing flare tool, and maybe some nitrogen (how does one buy nitrogen?). That's a few hundred dollars, but much less than the cost of paying someone to install one of these, and I can use the tools again if the other units which are 15+ years old stop working and need to be replaced.
Has anyone here installed one of these? Is there anything difficult I'm missing? Running all the lines will be labor intensive to make it look good, but probably not particularly difficult. Purging the lines and making sure it doesn't leak is important, but also tdoesn't sound too difficult.
This is on the third floor, and I'll probably want the compressor at ground level, so I'll need a system that can pump refrigerant up at least 30 feet.
Would it be worthwhile to take out the other two mini-splits and put in a single compressor that can supply three indoor units? I think that would be more expensive, and if a measured amount of refrigerant needs to be added, that might be beyond my DIY skill level. The old units are only about 10 SEER, but the first two floors have so little cooling load that it probably doesn't even matter.
Any chance I might be able to find someone to come out and just do the refrigerant work if I do everything else? I know a lot of companies don't like anything to do with DIY work.