Installed a 4/5 Ton Mr Cool (Gree Flexx) Heat pump

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
My system is now undersized. Original insulation for 1968 added 1000 sq ft and a big glass garage door. What I’m thinking is two 12k btu Mr cool mini splits. One downstairs and one upstairs. The upstairs really isn’t needed right now.

Think how many days a year your current system is inadequate. Me it’s probably averaging 3 days a year. It has to get cold and then not get above freezing during the day. I’m ok running my 10kw auxiliary strips for those three days.

My requirements when I upgrade are going to be different if add the mini split. If I do. It’s going to be two stage 4 ton unit. No mini split it will be a variable output 5 ton unit. Both will have 10kw of electric auxiliary heat.

my duct work is only sized for 4 tons. I maybe could by with 5 but I’d better run the really cheap fiberglass filters as one it hit full output I probably would have to much restriction to puts 1750 cfm let alone 2000!

As cheap as the Mr cool DIY mini splits are it’s likely that two 12k btu units are the most economical option now and possibly longer term if your ductwork isn’t sized for a big single unit. My other thoughts on this route are if you use the mini splits they probably reduce the runtime of your existing unit extending its useful life. As I recall you have the 16 seer Trane. 4 tons? It’s rated at 2.7 cop at 17F (or something close) and has a capacity of 26k btus at that temp. Two mini splits nearly doubles your heat capacity!
 
If you guys can afford it and can do it yourself, Mitsubishi is the gold standard. I did mine a few years ago
I looked into it. You would only need to buy a few new tools, but you might have no warranty. I know a good contactor and would probably just pay them. If you have a 10 year warranty that's worth something. At least with the home owner kit they still cover you for awhile.
 
Fortunately the DeLonghi AC is on wheels and can be rolled to the side for storage. It only gets used a few times a year right now, but things are warming up. The main issue is my knees which are rebelling more. Going up and down stairs on a bad day is not fun. Same goes for wood loading in the winter. Right now the problem is intermittent, but the handwriting is on the wall.
 
If you guys can afford it and can do it yourself, Mitsubishi is the gold standard. I did mine a few years ago
Mitsubishi, Daikin, American Standard, and possibly Midea are all on the options list. The difference in cost between brands is not huge but finding a competent contractor in our rural area can be a challenge. We got the first estimate and it was breathtaking for a basic swapout. $22k, for the Midea, $24.5K for the Mitsy, and $32K for the Mitsy split with a wall wart in the MBR. Nice profit when you consider that the cost of the condensor and air handler is $5k or less. I don't tink so Lucy. At that price I could hire a butler to run the stove. More coming.
 
Last edited:
I have a 4 wall mounts with a branch box, 3 ton hyper heat condenser. FS series wall mounts. All communicating units. It wasn’t cheap. All said and done, I was in it about $19K with tooling. I got quotes for over $30K to do this. No duct work in the house.