Pioneer Air Conditioner WYS012A-20 Wall Mount Ductless Inverter+ Mini Split Heat Pump, 12000 BTU-110/120V

Great product. If you are mechanically inclined it’s an easy installation and setup. If not seek professional assistance. Comes complete with all necessary equipment and parts.

Great so far. I'm using this in a 250 square foot attached garage with a concrete floor. I insulated the ceilings. The back wall is insulated, the garage door has insulation built in. The side walls are uninsulated have no windows. I waffled quite a bit on whether to get the 9000 btu or the 12000 btu system. There isn't really a reason to choose between the other based on price.I read about the risk of picking too large a BTU, since the system might have to cut on and off. However, this is an inverter system so it operates in a BTU range. I you compare the 9000 and 12000 btu spec sheet, the lower BTU range is only a few hundred BTU's apart which means the 12000 system should operate very nearly like the 9000 system on a mild day.I went back and forth quite a bit on the BTU sizing decision. It's hard to decided based on the various possible factors what the perfect size is going to be. From what I can tell, I don't think it's going to matter in my case, except, perhaps on the colder winter days. I fully believe this will put out plenty of cold air and will be fine on the hottest days of the year, but I'm curious to see if that'll be true of the heat.If I had to do it again I'd probably go with the 12000 BTU unit I guess, but I live in warmer climate so winter isn't really what I bought this for. Also, I can always just plug a space heater in for the occasional super cold day if needed. I did see on the spec sheet that the EER rating on the 9000 BTU was higher than the 12000, even though the 12000 has the higher seer rating. Seems like that might mean the 9000 is slightly more efficient at cooling than the 12000 model.The installation was reasonably ok if you're handy. I had an electrician do the wiring to a shutoff box outside and had an A/C guy do the evacuation. I installed the outside unit on some of the exterior mounting brackets sold for mini-splits. The hardest part was drilling a 2.5 inch hole through my hardiboard siding.I think if I had a vacuum pump I could have done the line evacuation myself. However, there was a nick in one flared end on the kit that was sent with this unit. It didn't cause me an issue because the A/C guy quickly reflared the connection. But, it would have postponed the install so I could deal with it if I was installing alone, or, if I had gambled that things were ok it likely would have leaked all the coolant out after I installed it and I would have had to pay an A/C person to come out and recharge the line and find/fix the leak.This unit looks great on the wall. It's completely quiet outside. I run it all the time and my last electric bill didn't appear to go up much, but it hasn't gotten consistently hot yet. The setting to alternate the fan direction is good.The "auto" setting is a bit twitchy. Sometimes it runs A/C and then blows heat a bit later on or vice versa, but that could be somewhat related to temperature changes outside.

I am a retired engineer that designed, and built my 3,000 sq ft, passive solar, earth contact home over 30 years ago. I had been considering replacing my 24,000 BTU, through wall heat pump, that serves our main lower 2,000 sq ft of living area for over a year. This June my heat pump decided to die. It was only 3 years old, and under warranty. Over a 4-month period, through the entire summer, the warranty company sent a repairman out 3 times with wrong parts. Needless to say, it was a long hot summer, and thank God the house is earth contact. Looking ahead I thought this was the time for a mini split, and found that Pioneer was the best choice for me.Now the installation problem. When I designed the passive solar home, in 1988, it has a lot of casement windows that look out on Lake of the Ozarks. There is not enough space to place any manufacturers inside equipment. The removal of one window, in a set of five was necessary.Installation of my 24,000 BTU Pioneer equipment was easy. It is a Model WS024GMF120HLD. The inside unit makes no more noise than a summer breeze, and the outside unit we never hear in the house. Even outside the unit is very quiet. What will be interesting is how much we might save on electricity. Two years ago, I replaced my 50 gal elect hot water heater with a heat pump equipped 50 gal water heater, and it saves us about $30 a month. Our average electric bill is about $135 a month, so because of our existing efficiency I don't expect a large drop in usage, but time will tell.The warranty company finally sent me a new replacement through the wall heat pump after 4 months. It sits boxed in my garage waiting for a new owner from Craig's list. I now have a modern unit that as a trained engineer / auto mechanic I don't need to depend on a A/C service call in a month.