To save time we had the mini-split delivered to my home. It came with easy to read and short mounting and installation instructions well worth reading.
The first task was to measure for and drill a 2.5" hole in the wall of where I mounted the blower and control unit. Drilling the hole in an old stucco house was the most difficult task of the job.
Rather than running the electrical along with the refrigeration lines, I used plastic conduit (HOME DEPOT) and then tied the refrigeration lines to the
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conduit with plastic straps. Two solid 4" concrete blocks were used to mount the compressor unit, and ensured they were level - using shims and a silicone concrete patch caulk.
Using a mini-split also allowed me to provide electrical service with the circuits we had been using for window units - so this was as simple as running some romex and installing a 15 amp plug with a switch at the plug.
As per instructions, with all the fittings tight, but not over-tight, it was time to use a vacuum pump to remove the moisture from the coolant lines. With a purchased vacuum pump, I quickly found the connection on the compressor is an ISO fitting rather than an NPT thread. I searched for a connection fitting, but found it would take time to obtain it. However, with an extra NPT hose, I was able to cut about 1/8" off the brass female fitting, allowing it to seat sufficiently to allow the vacuum pump to work. Since the NPT and ISO fittings appear the same, it is tempting to not force the NPT fitting on the ISO service fitting - not a good idea.
While vacuum pump worked this gave time to complete mounting and supporting the electrical lines. The control wires are fitted with plugs making this connection very easy - anyone familiar with home wiring can figure this out.
I gave the vacuum about 30 minutes - more than suggested, but more vacuum did not hurt anything.
Now, the fun part - as per the instructions, I opened the liquid side fitting for 10 seconds (with an Allen-wrench), closed it and checked for leaks using a soap spray at the fittings. No leaks - and then opened both valves, and then switched on the power, and then went to the inside to enjoy the quiet and cool start-up. Both units are extremely quiet. You can hardly hear the compressor unit operating standing next to it.
I am very pleased with the install and operation of the mini-split. It came with most of the parts needed for install, and I love the fact I did not need a professional to install it for me. The skill level was in line with automotive repair - say a brake job - only cleaner.
I know this is a long review, but my old house is not suited for central air. Contractors tried to promote the idea of using mini-split blowers on the inside, but all tied to a large honking compressor unit (noise and more noise). This also meant I had to install a separate electrical supply for this honker. Price quoted - $27,000.
I figure 4, 12,000 btu mini-splits will cool my house, but we may have to re-think this as the 12,000 btu unit seems significantly more efficient than my window units, leaving the only reason to install four mini-splits will be to gain zone cooling.
1. Be careful and take time to measure twice and cut once.
2. Don't over-tighten coolant joints.
3. Ensure you can provide a dedicated circuit to feed the unit.
4. Buy or rent a vacuum pump, and ensure you have fittings for NPT and ISO connections. My trick worked, but???
5. Take the time to install the coolant and electrical lines in a manner that will last the test of time.
Be safe and careful, and if you reach a frustration point, stop and research a solution.