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Community and Q&A

One Fujitsu minisplit vs two MRCOOL DIY

etting | Posted in Mechanicals on
I’m deciding between one Fujitsu 15LZAS1 15,000 BTU ductless and two MRCOOL DIY 12,000 BTU minisplits.  The Fujitsu is clearly the superior product and well sized for my house and climate, but the cost of having it professionally installed is prohibitive for me, and I would buy the tools needed to install it myself rather than try to get a pro to vacuum the lines, etc.  The 18,000 BTU MRCOOL has a minimum output that is well above my typical daytime winter heating load, so it would cycle on and off too much then, but the 12,000 BTU have a minimum output that is low enough to prevent cycling.  I can get two 12K MRCOOLs for roughly the same cost as one 15K Fujitsu, including all of the installation materials, and one big advantage of having two units is that if one fails, I’ll have the other to keep the house reasonably livable till I can replace the failed one, especially in summer, as I don’t have a window that can accept an air conditioner.  One 12K MRCOOL will heat and cool adequately on its own at least 75% of the time, possibly much more if loadcalc overestimated my loads, as Dana has said it tends to do.
I’m in central Arizona.  Typical winter days drop to 30 or so at night and then rise to 50 or so; it very rarely gets colder than 20.  Summer days usually hit the 90s and drop into the 70s at night; it can hit 110-115 several days a year.  On loadcalc, I used Roswell, NM as my location, as its climate is most similar to mine of the choices available.  I entered my wall insulation as R21 with R6 foam, the closest I could get to my R30 double-stud walls insulated with Rockwool.  With “good” tightness and 50 CFM of ventilation, I got 12,334 BTUs for sensible cooling, 200 for latent cooling, and 11,218 for heating.  It’s a 960 sf house with 8′ ceilings, one story with an open floor plan.
The Fujitsu is a great fit with plenty of capacity, minimum outputs that would prevent any cycling on and off, and excellent efficiencies: 
Maximum Heating Capacity (Btu/hr) @5: 21,000
Rated Heating Capacity (Btu/hr) @47: 18,000
Rated Cooling Capacity (Btu/hr) @95: 14,500
COP 6.06 at 47 degrees
COP 6.06 at 95 degrees
min BTU at 47: 3100
min BTU at 95: 3100
SEER 25.3
HSPF Region IV 13.4
I would be careful enough to install the Fujitsu properly, and I could get free EPA certification to handle refrigerants if needed, but I don’t know whether the relatively inexpensive models of vacuum pump, gauges, etc. I would need are adequate, and I’m reluctant to buy the expensive tools that are most recommended, given uncertainty about being able to recover much of the cost by selling them after I’m done.  If the Fujitsu failed, I would have no warranty protection, and if I had to replace it, I would need the tools again.
Two 12K MRCOOL DIYs would also seem to have enough capacity and would not cycle if I kept one of them off most of the time, but they’re less efficient:
Maximum Heating Capacity (Btu/hr) @5: 6,384
Rated Heating Capacity (Btu/hr) @47: 12,000
Rated Cooling Capacity (Btu/hr) @95: 12,000
COP 3.39 at 47 degrees
COP 2.46 at 95 degrees
min BTU at 47: 3235
min BTU at 95: 1341
HSPF Region IV 10
I can install these easily myself without any special tools.  I haven’t installed drywall yet, so it would be easy to run a new circuit for a second minisplit.
How would you weigh these two options against each other?
If anyone has done a minisplit installation with a reasonably inexpensive vacuum pump, gauge set, etc., a list of what you used would be a huge help to me and everyone else considering installing a system that requires these tools.

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  1. kyle_r | | #1

    I have installed a ductless and ducted Fujitsu myself, up to pressure checking and vacuuming the line set. I hired a small local hvac company to do this step for $200 per unit.

    1. etting | | #2

      Thank you, Kyle. The vacuuming and pressure-checking are the key tasks that the DIY MRCOOL doesn't require.

      1. nickdefabrizio | | #3

        Check out the Perfect Aire 18k DIY (e.g., 3PAMSHQCO18). I believe they are a slightly newer generation than the MR Cool and are slightly higher efficiency according to NEEP. HVAC Direct has them for $1824. Of course, the Fujitsu units are great (I have two low temp 12k units that work great). If you can put them in yourself, you can pick them up from HVAC Direct for around $2400 (when you include the line sets). But around me, professionally installed these are closer to $ I am considering the Perfect Aire model for my basement.

        1. etting | | #4

          Thank you, Nick. I'm giving Perfect Aire a close look, as their specs do compare well to the MRCOOL. They're around 50% more expensive, and I haven't found a lot of reviews yet. I hope someone here will report their experience with them.

          1. nickdefabrizio | | #5

            Are you sure about the pricing? HVAC Direct has both MRCOOL and Perfect Aire, and MR COOL seems a bit higher. In any event, I think you will find that they are very similar but the Perfect Aire units may be a more recent version. If you look at the AHRI spec pages, they include another generation of MRCOOL DIY models with slightly higher specs that match closely with the Perfect Aire models..... I called MRCOOL and they said that these higher rated MRCOOL models are a new generation that have been tested but have not been released to the public yet and will probably be released late this year.

  2. etting | | #6

    Thank you again, Nick. The MRCOOL are much more expensive at HVAC Direct than at a few other retailers, at least one of which has a coupon that lowers their price to around $1200. I won't be able to wait till late this year for the new MRCOOL, but I'd be interested to see the specs if you have a link. I couldn't find them at the AHRI site.

    1. nickdefabrizio | | #7

      the AHRI ref numbers are 207339187 and 207339188 (see certificates below). Note that these units have a HSPF of 11.5 versus 10 for the previous units and a designation of "C" at the end, not "B".

      I found HVAC Direct to have good prices for MRCOOL. Where did you see better deals? Thanks

      1. etting | | #8

        Thank you for the certificates. Overstock and Home Depot have the MRCOOL DIY 12K for around $1400, and you can get 15% (around $210) off at Overstock by signing up for their emails.

  3. STEPHEN SHEEHY | | #9

    The much greater efficiency at 95° would push me to the Fujitsu. COP 6.06 v. 2.46. Unless I misunderstand something, doesn't than mean the Fujitsu will use less than half the electricity?

    1. etting | | #11

      Thank you, Stephen. Interestingly, the difference in cooling costs is much smaller than those COPs would suggest, at least according to the following. If you enter a SEER 22 (representing the MRCOOL) and a SEER 25 (representing the Fujitsu) into the following calculator, using Roswell, NM as the climate closest to mine, it shows a difference over 15 years of $131 at 12.51 cents per kWh. It's a 12% difference rather than the more than 200% difference the COPs would suggest.

      I entered the exact SEER, HSPF, and BTU capacities representing the two minisplits into the calculator below, again using Roswell, and it showed an annual difference in energy cost at 12.1 cents per kWh of $8.

  4. Expert Member
    Akos | | #10

    Most of the off brand mini splits are made by either Midea or Gree. The units used tend to be form their budget line. Besides the hit in performance, there could be durability issue as well down the road.

    I will be replacing a Freidrich mini split (I believe it is a bargain basement Gree unit) that the electronics have died in after 5 years at the cottage. In retrospect, a better unit would have been worth the extra cost.

    1. etting | | #12

      Thank you, Akos. The MRCOOL 10 HSPF is at the low end of the range for Midea and Gree, but its 22 SEER is roughly in the middle of the range for 12,000 BTUs. I've read suggestions that the lower performance numbers might be related to what they need to do to make them DIY, but I haven't seen that explained. The thousands of reviews for MRCOOL DIYs at Home Depot and other retailers average around 4.5/5 stars, but few of them probably speak to durability, as most people leave reviews fairly soon after purchasing. Do you have any evidence that the MRCOOL minisplits lack durability?

      1. Expert Member
        Akos | | #13

        My point is that there is a good chance that a Fujitsu unit will make it to year 15.

        If buying outside of Mitsubishi/Fujitsu/Daikin, I would at least try to get the higher tier unit such as a Gree Sapphaire or Midea Infinity/Advantage. These only cost a bit more than a budget unit and you get much higher Seer and HSPF.

        Some of MrCools unit are actually quite impressive, their Universal ducted heat pump looks like an excellent product.

        1. etting | | #14

          Thank you, Akos. I would be interested to see any evidence that a MRCOOL DIY won't make it to 15 years. I would probably spend more on a higher-end unit if it were DIY. The Perfect Aire DIY have some better performance numbers, but too few reviews to get any sense of their quality control. Outside of DIY, I would just stick with Fujitsu.

  5. rustyshackleford | | #15

    I am facing similar choices, in this case between a Fujitsu 18K unit and a BlueRidge 18K unit. The Fujistu is only about 10% more expensive (at e-comfort) an clearly a superior product, both in terms of performance (efficiency and cold-weather capability). But I'm told that if I buy it from an online place, that I'm SOL on warranty. Apparently it has to be bought through a licensed contractor.

    So, do I buy the Fujitsu, install myself, with a local guy who'll do the freon for $200 or so ? And hope nothing goes wrong. Or install the inferior BlueRidge product the same way, understanding that BlueRidge is very friendly to DIY installs ?

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