There was an episode of Ask This Old House a week or so ago where they installed a minisplit for a customer. It was a single-car garage that the customer wanted to use as a home office (it was insulated). I thought the installation was pretty simple: 1. Locate and put a mounting bracket on the inside wall for the inside unit using a couple of screws. 2. drill/cut a 3" hole through the wall and place a sleeve (supplied) inside. 3. Set the inside unit up on the wall. 4. Locate and place the outside unit on a pad (purchased) outside. 5. install the bottom half of a plastic channel (purchased) to hold the wiring and lineset to the side of the house. 6. run and connect the 4-wire electrical line between the two units (purchased). 7. run the power line from the outside unit to the main power panel. 8. run the lineset from the outside unit to the inside unit. Surround the lineset with (purchased) insulation. Snap the top part of the plastic channel in place over the lineset and wiring. 9. Connect the lineset at both ends using the proper flare fittings (supplied). connect a vacuum pump to the service port on the outside unit, pump down and check for / repair any leaks. (You'd need a pro to do this.) Connect the main power line. open the inlet/outlet valves for the refridgerant on the outside unit. (refridgerant is already supplied with the unit.) Turn it on and cool down. Enjoy a frosty beverage of choice. This looks a bit more complicated than it is. But if you're a DIY person, you can do a lot of it yourself. Then an AC guy can come and take care of the lineset and powerpanel stuff.

Hello, Would like to know how many BTUs (for 1 wallmount system)would I need for two floors of 690 sqfeet (each floor). The Unit will be on the 2nd floor in the middle between 2 bedrooms and a washroom (over washroom door facing master bedroom). It will be a dual split system. ------------------------------------- Also would like to know which is a safe reliable cost efficient brand, example of wall mounted (split systems) air conditions I've heard of: Fujitsu (they give 10 years warranty parts and labour) Mitsubishi (6 yrs parts and labour however been making them longer) Daikin (6 yrs parts and labour) Igloo York Carrier Grey All about the same price... ----------------------------------- Finally, is it better to get a dual system (with heat pump), from my understanding they are almost the same price and the advantage is that it has a variable BTU which may save some $$. Since the heat pump will be at the higher level then it wont heat as much however it is coming at about the same price. Then again more electronics in a system more chances of malfunctioning sooner? Thank you, Stelios

"Why someone would buy Mitsubishi/Carrier when there is much cheaper option." Because Mitsubishi is an established brand with a good reputation - the others are...... well....... as a rule, an unknown. Note that you can buy a Mitsubishi Mr Cool DIY system for around $1500, but finding a reputable installer may be a challenge (because they can no longer bury the labor charge and/or can't mark up the equipment). The smallest Mr Cool, I believe is 12,000BTU which is too big for your needs. Mitsubishi make smaller units but not in the DIY series, so you end up getting screwed by the contractor again!

You might be able to put the compressor unit on the balcony, and then feed refrigerant to a unit on the inside wall abutting the balcony. Let it cool everything, or else you have to pay for more expander heads and the plumbing. Also the heads have to drain, and I will be happy to regale you with possible issues associated with doing so. A few years ago (in NH) I had installed two Mitsubishi systems, one 4-head and one 2-head. Four of these heads are on interior walls. I think the price was near $20k to cool 2600 sq. ft. If you are only supplementing the building AC in the summer, and doing moderate cooling in the fall, you may not need a very powerful unit. I can say that the compressors and the heads are very quiet. You can hear the fan at the outdoor compressor. It is about as loud as a window fan on low. At one point one compressor developed an intermittent racket, fixed by some adjustment, when the compressor iced up trying to pull heat from near freezing humid air. They are designed to de-ice, but I think between fan alignment and ice build-up there was a bit of overlap that needed to be adjusted. You will need a hole in the wall to contain two refrigerant lines and a control power line. The lines to the compressor unit will be covered by a plastic cover. You will need an outdoor disconnect switch and power feed of 20 to 40 amperes at 240 Vac. Your balcony may be subject to a warm air breeze from the compressor unit, depending how it is placed.