A simplified step-by-step description of ductless air conditioning installation process*:
Make sure to protect the area with plastic or fabric drop cloth. Start with indoor ductless air conditioning installation. Carefully unpack the indoor unit, remove the mounting bracket and hold it to the wall.
Level it, then mark the screw hole locations and where to bore a hole for the refrigeration lines, condensate discharge line and electrical cable.
Screw the mounting bracket to the wall, making sure it’s level, as it is important for condensate removal. If not properly installed, the unit will collect condensate water, develop algae and mold. From inside, bore hole into the wall with rotary hammer and 2-1/2-inch to 3-inch diameter masonry coring bit. Once the bit’s pilot penetrates the wall, finish boring the hole from the outside to avoid wall chipping.
Proceed with indoor ductless air conditioning installation on the wall-mounted bracket. Pass the refrigeration lines and condensate discharge line through the hole in the wall.
Attach a plastic protection duct directly below the hole on the exterior wall; the plastic duct will hide and protect the refrigeration lines, condensate discharge line and electrical cable. Use adjustable wrenches to remove the compression fittings from the ends of the copper lines.
Carefully bend the copper refrigeration lines down into the protective duct. Slide a brass nut onto a new length of copper tubing, then use flaring tool to flare the end of the copper tubing. Hold the tubing’s flared end against the end of the refrigeration line coming from the air conditioner. Hand-tighten the nut to hold the copper tubing to the refrigeration line. Repeat to attach the remaining refrigerant line.
Proceed with the outdoor ductless air conditioning
installation. Set the outdoor condensing unit onto a level pad adjacent to the plastic duct. Use two adjustable wrenches to tighten the compression fittings on the refrigerant lines. Then wrap pipe insulation around each line.
Run NEC approved power whip from an outdoor electrical box to the condenser unit, and communication electrical cable from the outdoor unit through the hole in the wall to the indoor ductless air conditioning unit. Snap the cover onto the protective duct to conceal and protect the lines and cable.
Make all electrical connections at condenser and at air conditioner, then pressure test the system with nitrogen to 300 pounds per square inch. Vacuum out the nitrogen, then open valves to release refrigerant into the system. Turn on the electricity and test the air conditioner.
* Note: this description is for familiarization with the ductless air conditioning installation process, should not serve as a substitute for complete installation manual. Any person attempting a ductless air conditioning installation should study the specific installation manual. Check our library of installation and service manuals
See more ductless air conditioning installations in our installation gallery