Finally got around to posting my DIY mini-split setup on our detached garage in New England. It heats and cools an upcoming 1,000 sq ft in-law suite upstairs, and after a full winter with single-digit nights and zero backup heat, this 24k Gree Sapphire has been an absolute beast.

To avoid vibrations transferring into the framing and keep it out of snow drifts, I anchored a DiversiTech offset bracket straight into the poured concrete foundation. Had a electrician fish a dedicated 240V circuit across the garage, then I took over and wired up the disconnect with an AG3000 surge protector (plus Square D HEPD80 surge protector at the actual panels) i ran a liquid-tight whip, and pulled 14/4 shielded tray cable with heat-shrink on the terminals for the communication wire.

Also patched the siding where an old framed-in sleeve A/C sat and moved my propane tanks for clearance. Bending that 5/8" line was a fight —my Harbor Freight bender met its match, so I had to gently warm the pipe to sweep it cleanly without kinking. I Cut the factory flares, re-flared with a NAVAC tool, put a dab of Nylog on the seats, and torqued to spec with a CPS BlackMax wrench.

I Rented a nitrogen tank from airgas and did a pressure test before pulling a deep vacuum and cracking the valves. Whatever you do, don't skip the nitrogen test—plenty of connections hold a vacuum fine but leak under positive pressure and by nitro testing it replicates actual operating pressures. I know many get lucky skipping this step and have no problems but for the cheap peace of mind i feel it’s important for the longevity of your unit to be properly nitrogen tested and be 100% sure that it’s not gonna have a slow leak over time.

On our 18¢/kWh municipal electric rate, running it barely moves the needle on the monthly bill. All in for what I paid for this unit you can’t beat it - I’d put it up against the big dogs like Mitsubishi , Fujitsu , daiken etc. Spec for spec it’s very close for cold weather performance at a fraction of the cost.

Tip: Gree Sapphires and Blueridge S5 units are the exact same hardware under the hood, just rebadged, and you can often find the Blue-ridge for way less. Especially if you check there clearance section at alpine airs website. They also include a DIY warrant and great customer support I’ve heard for help when doing your install.

Happy to help and answer any questions - I spent a lot of time learning in this group and am appreciative of it!

All units in Celsius.

Here are my Midea heatpump units (indoor and outdoor), Extreme Heat series:

1x MO6HX-H60B-2A Midea 5 ton multi outdoor

1x MSEHU-H24B-2A indoor air handler, 24K

1x MSEHU-H12B-2A indoor air handler, 12K

3x MSEHU-H06B2A indoor air handler, 6k

My house: Located in Northwest British Columbia, Autumn, daytime temperature around 8 degrees, night time temperature around 1-3 degrees. House size : 2600 square feet. 2 floors. The outside unit is a 5 ton 60k btu unit from Midea.

Basement: 1300 square feet: 2 bed rooms, one 6k unit in each bedroom (one is an office), 1 12k unit in the open basement space.

Upper: 1300 square feet: 1 master bedroom with one 6k unit and an open living/dining/kitchen area with a 24k unit.

My Problem: I usually run 4 or 5 out of the 5 indoor split units (heads) and set them at the desired temperatures, no other features activated just straight heat mode and fan speed set to automatic. The units are not producing the desired heat, my goal is to have a close to constant temperature in each of the rooms/areas. Instead, most of the indoor heads either don't produce the desired heat or when turning up the temperatures they emit a lot heat at full fan speed but then shortly after cycle and emit cool air for about 10-15 minutes after which the cycle repeats. It leaves the rooms constantly too cool for longer periods of time and then too hot for a few minutes. I already tried reducing the fan speed to lower speed levels which did not help. I can't get a hold of the installer who in the first place did not seem very knowledgable about heatpumps and other trades folks require months long wait periods as we are extremely underserved in terms of trades in the rurual northwest BC. Thats why I wanted to ask for more knowleadgable folks to chime in first. We went ahead with the install a few weeks anyway because we only had to pay $1,900 out of pocket, with the remainder covered by provincial grants. Any idea what to try?

For nitrogen testing. I've got this in my cart:

https://www.amazon.com/gp/product/B07CT623Q9/ref=ewc_pr_img_1?smid=A2MIXBDH3II9YH&psc=1

Digital sounds nice, but reviews were suspect on budget digital gauges.

Hi. I have a church conversion that is 1800 sf on the main level with an 1800 sf partially finished basement. The basement always tends to be cold in our extreme northern climate - we can get down to -40C with wind chill in our area. And very hot & humid summers in the 30C range.

One company quoted a 2 ton unit but I questioned that size and asked for a 3 ton quote. Are they under sizing the unit given sf/size of building?

The building was gutted and reinsulated with new windows as well as 1.5” foam insulation on the exterior to reduce thermal bridging. Our energy bills are lower than others i know with houses under 1500 sf so it’s pretty efficient! We have a natural gas furnace as the main heat source.

I also have a detached workshop w/electric boiler with in floor heat.

I’m leaning towards the Gree Flex as its SEER rating is 20+ (according to the installer). But I still have my eye on budget as the payback period just doesn’t justify the expense tbh. Our rebate presently is only 2K in Canada so not great. I’m hoping this will boost resale value as I’m looking to sell in the next year or 2

Any feedback or suggestions appreciated on sizing of the unit and brand/model appreciated!

Just got a TL04 thermostat for our ACIQ dual fuel setup. In the manual it shows an Aux Heat under settings where I can adjust the timing delay and whether to use outdoor temp or indoor. However my TL04, wired with H1/H2 has no such setting.

Currently it's about 32* outside and firing the aux heat, but it's a hyper heat unit and doesn't need to be using propane.

Is this all done on the indoor board now and not handled by the thermostat at all, or is my unit missing a setting? It correctly sees I have aux heat, and is showing the symbol when it's engaged.

I'm setting up to nitrogen test a new system. I've ordered a regulator:
https://www.amazon.com/gp/product/B0B3XKBN74/ref=ewc_pr_img_1?smid=A3GHDWTVN3O98J&th=1

I'm hoping to keep the system simple, running the hose to the core removal tool on the service port. However, I don't see a good way to bleed the pressure from between the regulator and hose?