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Mitsubishi rep says minisplit won’t work … back to geo?

user-1012653 | Posted in Mechanicals on

So after recommendations on here and other research, I have been in communication with a Mitsubishi rep and a local installer on my new house design. Currently it is roughly 3200 total conditioned square feet (single story with walkout basement). R values are roughly 15,30,40,60, with 7400 HDD in zone 6. Current loads are around 20-22k we think (hope). The plan was to use a single unit with 4 heads. 2 up and 2 down. 1 ducted unit to serve 2 bedrooms and 2 bathrooms, then a wall unit to serve an open living, dining, and kitchen. Similar situation in the basement.

However they are saying this is not going to be cost effective at all. The standard mr slim units are rated to around 15 degrees requiring electric base boards to pick up the slack, which would be expensive I assume.

Their hyperdrive is a one to one unit, so no zoning but rated to -15. They are also saying they cost around $8k each vs nearly 8k for the entire assembly! Even if we eliminated 2 of the heads, and use one up and one down, that is still more expensive then geo.
Geo is around $20k before credits from feds, local utilities, and state. After credits, it puts it around $12k. I was also planning on using the desuper to dump into the electric waterheater to pick up some of the heating as well. (although minimal I realize).

What are the pro’s thoughts on this?

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Replies

  1. user-788447 | | #1

    Some of my colleagues had similar systems sized for a comparable home in zone 6. The bids they got back yielded the same result - the mini split distributed with multiple heads was outrageously expensive over twice the cost of the ground source setup.

    Seems like for residential applications only a single point source mini split is priced reasonably.

    Read this blog entry about a group of homes that combine a air source heat pumps with some electric radiant panels for backups:
    http://blog.energysmiths.com/2011/07/results-of-the-first-year-at-8-zero-net-energy-possible-homes.html

  2. user-1012653 | | #2

    I agree. I feel the ground source is a "greener" option too.

  3. GBA Editor
    Martin Holladay | | #3

    Jesse,
    Prices on ductless minisplit installations vary widely across the country. In areas of the country where these systems are new and there isn't much competition among contractors, prices can be twice as high as they are in areas of the country with more competition.

    Check prices on one of the Fujitsu units. In Massachusetts, several builders have put in single-zone ductless minisplit systems for $3,000 to $5,000. Marc Rosenbaum told me, "We put in a ducted minisplit system in Newton, Massachusetts -- a Mitsubishi three-zone system, ducted upstairs. The system included a Renewaire ERV tapped into the air handler. The whole system went in for $13,000 -- a complete HVAC system." There is no way you are going to get a ground-source heat pump system for that price.

  4. user-1012653 | | #4

    Martin
    The problem is they can get the Miti system installed for around $8k...4 heads on 1 compressor which is a GREAT price for an hvac system for 3200 sqft...this includes the HRV. However its only rated to 15 degrees they claim (and shuts off). During winter we have gone for weeks in a row with temps below that. We would need other electric heat to make up the slack, which would probably be base board heaters, which look really ugly and as you know expensive to run. Their hyper units are rated to around -15, which would be ideal. However they are a one to one system, so if I need at min. 2 zones (main level and basement) I need 2 compressors. He said install is around $8k EACH, plus HRV, making it closer to $18k.
    For a 2 ton Waterfurnace COP5 with horizontal field, ducts and HRV, I was quoted $19,900. 2 other similar bids were right around 20-22k. Minus the Feds 30%, plus about another $2k from local utilities, this puts my final price at around $12k.
    Do you know what the Fujitsu units are rated at by chance?

  5. GBA Editor
    Martin Holladay | | #5

    Jesse,
    For very cold temperatures, you probably can't do better than the Mitsubishi Hyperheat. The Fujitsui units are only rated down to 0 degrees F. The Fujistsu 24RLXFW has a heating capacity of 24,000 Btuh at 0 degrees F.

    If you can get a ground-source heat pump installed cheaper than a ductless minisplit system, then that may be the way to go for you.

  6. user-1012653 | | #6

    thanks Martin
    they still may be worth looking into. With down to 0, I would think the heat loss in the house would be pretty minimal during the times it dips below that, and it does not stay that low for very long.

  7. wjrobinson | | #7

    GSHPs costs near me have run $45-100,000 with expensive service contracts etc. And I think COPs are half your stated 5.

    $12,000 for a COP 5 complete HVAC and hot water set up is far better than any other choice any of us could make. Your contractors need to send men this way to get our local prices down and our COPs up.

    I really would like to believe all the above is dead on, but am a skeptic. I need to see in person what the real numbers are.

    Anyway IMO, definitely go GEO. $12k is a fantastic price.

  8. user-1012653 | | #8

    The unit is a Waterfurnace Envision. Spec'd performance rating range from low 4 up to around 5 for the 2 ton. Obviously these are not real world tested numbers, and loop temp plays into that as well. The big item here is only the need for 2 loops is where a good savings is. I may put in a 3rd however.
    I guess I am not exactly sure what you are not believing?

  9. wjrobinson | | #9

    Jesse, in my area your numbers are not happening that I know. Not even close. Good luck. Do the $12k system COP 5.

  10. GBA Editor
    Martin Holladay | | #10

    Jesse,
    The main problem with the COPs specs that GSHP manufacturers list is that they don't include pump energy, which can be significant. Expect in-service COPs to be around 2.5 to 3.0.

  11. user-1012653 | | #11

    thanks Martin. That was sort of what I was suggesting in my earlier post. I am trying to get "real world" numbers from them. Only being 2 wells, they are looking into it. The Waterfurnace rep thinks the 4-5 COP will still be running near 3.5 on 2 wells. But I will certainly take that! I would even take 2.5 for that matter for full heat load. Still much better then the alternative...which is propane.
    thanks as always for everyone's help and input.

  12. wjrobinson | | #12

    3.5 then add in all electric loads for pumping fluids , fans, circulators, and the COP compared to baseboard electric is an apples to apples COP number Jesse. That number is better than baseboard but much lower than just the refrigerant fluid pumps ideal COP 5 or the 3.5 you recently changed to.

    The reason I say buy it is you prefer it and your price is very good and if it works you should get at least COP above 1 which is better than baseboard.

  13. user-1012653 | | #13

    3.5 is their estimated total COP taking into account all systems operating. I am saying I realize 5 is not how it performs. However the higher the starting point (5) the higher the final operating point is. 3.5 is what they are claiming it will run at in the end. The unit itself is rated at 5 COP however which is what I was talking about when I said a Waterfurnace.
    however thanks for your input, I agree, I think it probably still is the best system for the money.
    I am not sure why your costs are so high in your area. Horizontal wells cost about $1500 per ton with verticals being about $2500-3000 depending on depth. The equipment is around $10k for the 2 ton unit. I did talk to a contractor that actually ADDED 30% to his normal fee because "well you will get that back anyway from the feds". True, but the incentive is to help homeowners afford to install them. His method is countering that. His bid was instantly thrown out. Do they do that in your area?

  14. wjrobinson | | #14

    Jesse, where I live I have not heard of one GSHP system performing at COP 3.5, costing $12,000 for a 3200 sqft home and with people happy about the low air temp coming out of the floor registers. When I do, it will be my first day that I consider having GSHPs installed. Also I would like to see the day come when they and solar are affordable without a subsidy. Good luck.

  15. ZdRsx4MyBR | | #15

    Hi Jesse,

    I just moved into my home that is very similar to yours. (3000sq ft, 20k/hr heat loss, 8500HDD, etc.) We heated the home last winter while construction was going on with two mitsubishi hyper heat units and it was very affordable. They cost $5000 total to install, $2500 each. If you are in love with the GSHP then go for it, it sounds like you are getting a good deal. If you would like to talk to me about my experience with the hyper heats feel free to send me an email. gmink21 at Y a h o o. They work great and we are very happy with them! (They air condition too!)

    Graham

    ps I am not a dealer or installer

  16. JyKChUWn3u | | #16

    Graham,
    What part of the world is your home located? Zone? We are in the process of planing a new home in NW Montana. I, like a lot of other folks, am trying to determine which system(S) would be the most efficient yet affordable heat source. Our original plan was to have a HE wood burning fireplace ducted and blown to each end of the house away from the fireplace (which resides in the middle of the house) for our primary heat source. I would like a redundant system capable on its own of maintaining the warmth of the home through the long winter.
    The basement is a daylight basement then one main floor and a small loft. Total sf is 2200. All electric utilities. Zone 6 and elevation 4400 ft.
    I look forward to the forum's input on our dilemma/opportunity.
    Rod

  17. user-1012653 | | #17

    Graham-
    email sent. $2500??? wow. that was around the price of the standard Mr. Slim units.

  18. gusfhb | | #18

    The small hyper heat units sell online for 1600 to 1800 bucks. If your contractor is not competitive then buy them online hang them yourself and find an ac tech to pump them down and pressure test them.

  19. user-1012653 | | #19

    I am bring this back to life. I am working on my design to get the loads lower and get more south glass in rooms that did not have any previously. I am starting to think the mini split using 2 separate units (not zoned/multihead unit) is the way to go instead of geo. I am also looking into the Daikin products. Does anyone have any input on how they perform compared to the Mitsu huperheat units?

  20. gusfhb | | #20

    Mitsu and then the Fujistu Halcyon line are the only ones i have seen that claim low temp operation. Investigate the output at low temps,as it is a percentage of rated output. Also the hyper heat only seems to be on the 9 and 12k units.

  21. user-1012653 | | #21

    bringing this back to life...with some newer information. I believe the hyperheats are now available in a 21k btu unit, which would work great for my proposed home. Even at below zero temps, it should still be able to cover nearly 100% of the load of the main floor. The basement would have the 12k unit most likely.

  22. user-218720 | | #22

    Jesse,
    It's been a year, what system did you finally choose? What are it's benefits and how have your energy bills been compared to what you expected? Was it as comfortable as you expected?
    Thank you!
    Audrey

  23. user-1012653 | | #23

    Audrey
    We just got under construction about 3 week ago. I think we are going with a traditional gas furnace and AC. Main reason is the current rebates we can get from local utility companies. We can get up to $6150 back in rebates by going with a high efficient gas furnace. This actually puts the price of the installed system less then mini splits installed. We are doing full ICF from basement to truss with total r value average of 28. It is low compared to many standards here and even things I have said previously, but there are many reasons why we chose this system vs wood framing of some sort (thick foam, double stud, etc).

  24. user-865314 | | #24

    I have 2700 square foot cape ranch. Heers rated at 60. Have Mitshubishi City Multi with 8 wall units. Basement is 1500 sq ft and has a 20k Diakin. Daikin runs 24/7 keeps basement at 70 degrees with outdoor temps at 0. City Multi runs fine at 0. Never run City multi when we go to bed. Turn it on at 7 am.
    Keeps house at 70 degrees no problem. the house has 27 windows all oversized.

    I have a small cape in New Hamsphire it has City Multi with baseboard. City Multi runs at -10 degrees plus use makeup heat. My sisters total heating bill runs about 900 dollars a season including baseboard. Home has spray insualtion in Roof ans basement.

  25. Expert Member
    MALCOLM TAYLOR | | #25

    "We are doing full ICF from basement to truss with total r value average of 28. It is low compared to many standards here and even things I have said previously"

    Jesse, that comes as a bit of a shock after the extensive discussions you had here working out the details. Could you possibly briefly summarize what lead to the about face?

  26. JerryKing6 | | #26

    I just installed a 3 zone system using 3 single Hyper heat Mitsu units which cost me only 7500. If I had chosen a single compresser with 3 inside units not only would I have needed back up heat but the cost of the Mitsu HVAC units would have been with in 200$ of hte Hper units. This winter we had temps down below 5 degrees and the heat pumps had not problem keeping the place warm with the highest cost day being only 4$ to heat the house. I have removed my 4.50$ a gallon Kero furnace and hove not looked back. WHile this winter we had more single digit colded days this is so far a very good setup.

  27. JerryKing6 | | #27

    I am getting 3 Hyper heat units 2 9000 BTU and 1 12000 BTU unit for 7500 installed. I hope that maybe in your area.s the price has come down. This install is 100 Miles MW of DC. I most likely could have used a single compressor with 3 head units but we do get temps into the single digits once in a while, Our normal winter avg. is 23.1 at night and 37 in the day time, Normal winters do often get temps into the single digets several times a year adn goiing with the hyper heat I can get rid of my 4.50cents a gallon kerosine furnace which will only go up in price.

  28. Expert Member
    Dana Dorsett | | #28

    That is a decent installed price! In my neighborhood a pair of 3/4 ton Hyper Heat and a 1 ton would be running a bit over $8K, based on recent quotes I've seen.

    Using mini-splits to get off the higher-priced fossil fuels is both good short-term economics, and good for the planet too. Take a peek a this recently published policy piece from RMI about displacing heating oil use in the northeast:

    http://www.rmi.org/cms/Download.aspx?id=10410&file=2013-05_HeatPumps.pdf

    At $4 oil/propane/kerosene the price per delivered BTU is less than half what your fossil-burner delivers, even at pricy New England utility rates. With the mid-Atlantic's somewhat lower power costs and somewhat higher average efficiencies it's a slam-dunk kind of investment paying off in very short years (year one, if financed over a reasonable time period at low interest.)

  29. user-1012653 | | #29

    Malcom
    sorry for the 4 month no response! Have not been to this site in quite some time. Been quite busy. We are now 7 months into the build. So far I have not regretted the full ICF decision. Obviously there has been some things that needed changed and adjusted to make it work other than wood framing. There has also been some things that were slightly "out" being my first ICF build, but certainly nothing worth mentioning. All and all it is turning out quite well.
    The reason for the change was due to a bunch of pros and cons I generated between the options discussed over the years. First off, the total cost of ICF vs double stud framing, comparing materials only since I built it, was only 3-4k more. Having built many a wood home (never a double stud though) I guessed the vertical ICF would be faster. Having gone through it, I believe it probably was. My wife (with 0 construction experience) and I was able to get the foam up in just a few days. It was also very easy to do with no heavy lifting at all. Once the foam was up, we spent a couple more days bracing it. All in all, less than a week the walls were up, braced and ready to pour. There is no was I could have framed a double stud house, sheathed it, sealed it up, and insulated it in that amount of time. It took about 4 hours to pour each level.
    As mentioned, the whole wall r is around 28 for the system. In my zone 6, this is still well above code, not quite the r40 like the double stud, but running energy models the savings in energy was not as high as I would have thought. So the other benefits of ICF took over beyond energy costs.
    The nature of the system was inherently tighter. Still have not done a blower door on the system, but the HERS rater has gone through a few times and based on what he has seen, is quite anxious to see how it tests out. The system is stronger. Obviously there is nothing more to go into here. Its a lot stronger than wood. I am in tornado alley, and have been through half a dozen in my life so far. Also due to the strength, it will stay tighter for the life of the building. it does not rely on caulks and tapes to keep it air tight (nearly as much I will say). The solidness can also be felt in simple things such as closing an exterior door. It is very solid feeling without any vibration in walls like can be felt in wood walls sometimes. Water, wood, rot, insects, etc. All also things to consider. There is no box sill areas since the ICF runs footer to roof and the floor hangs off the inside. I went with Kolbe triple pane windows on the house. R60 blown in fiberglass in the attic after a spray foam attic seal. It is a very quite house.
    check out my building blog for more information. We are further along than what I have updated (we are drywalled and painted at this point).
    http://lizerhomestead.blogspot.com/

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