Mitsubishi or Daikin minisplit ductless?
user-6813968
| Posted in Energy Efficiency and Durability on
I am building a new construction house and will be installing a ductless minisplit system for heating and cooling. I have chosen this route because I want ductless and for energy efficiency.
My question is: Should I go with Mitsubishi or the Daikin system? Daikin costs less and has a better warranty. But what about performance and energy efficiency? Can anyone answer this question? Thanks.
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Replies
User-6813968,
To recommend the right equipment, we need to know your geographical location or climate zone.
It would also be helpful to know your design heating load and design cooling load (assuming, that is, that you have calculated your loads).
-- Martin Holladay
It's North Carolina Zone 4, no analysis has been done on the heating or cooling loads. Just want to know what equipment is more energy efficient.
Check out the Midea Premier (or the upcoming 40 SEER Premier Super)
Efficiency is highly dependent on sizing it correctly, and the local climate, and it varies from model to model within a vendor's suite of offerings. It's not to hard to guarantee abyssmal performance from any vendor & model by applying it incorrectly. It's also not hard to optimize the performance of equipment that wasn't at the top of it's class to do pretty well.
But if there hasn't been accurate aggressive load calculations (preferably performed by a third party, not an equipment installer) there's no good way to assess the quality of any proposals. Hire a professional engineer or a RESNET rater to run those numbers, and let them know being aggressive but accurate on the known factors, and aggressive their assumptions for the unknowns is more important than padding it out "just in case". Even with that approach it's more likely than not that the calculated loads will be higher than reality, but they'll be much closer to reality, which is the all important starting point for getting the equipment sizing right. In my area that service costs between $500-1000 (YMMV), but it will usually save more than that up front on equipment costs, and again down the road on operation cost.
Almost all proposals I've personally reviewed when there were no prior calculations were oversized for the loads., At least half were grotesquely oversized, and way too much equipment, making it far more expensive up front, as well as less efficient and less comfortable. A common idiot-attack proposal is to have a ductless head in every room in the house, each oversized for the room's loads, often with design loads a fraction of the minimum modulated output of the unit. A modulating heat pump that's never modulating, always cycling on/off will never hit anywhere NEAR it's tested efficiency numbers, be they really great numbers, or middle of the road numbers. Those proposals are pretty good for the installer's ability to make the payments on the yacht, but are not in the interest of the homeowner.
Both Daikin & Mitsubishi make some high efficiency equipment and some less efficient equipment- the model and application matters. But the number of local installers and the distance to the local/regional distributor or factory support center varies by region. Independent of efficiency numbers and sizing, going with a vendor with more local expertise and support is usually the better choice. eg: I live less than 20 miles from the regional Mitsubishi training center, and there are literally dozens of certified installers within an hours drive of my house, whereas there are maybe 5 certified Daikin installers in the entire state, none near me. Who do you think I should go with?
If you're not running the load numbers and you have some proposed equipment, for sorta-apples-to-apples pull the efficiency test submittal sheets (or post the exact model numbers and I'll dig them up when I have time). As a general rule, the unit that has the lower output at minimum modulation will be more efficient (and definitely more comfortable), and that's especially true if it's oversized for the design load.
User-6813968,
For more information on calculating heating and cooling loads, see this article: Who Can Perform My Load Calculations?
--Martin Holladay
The short version response #4:
This question feels a bit like "Which truck is better Ford or Chevy?"
The answer depends on what you need to haul, the model, and how fast it needs to go.
Start with the load, which is somewhat in your control for new construction, assuming you're designing it.
Only when you know the load is it possible to make reasonable choices on the mechanical systems required to support those loads. Any proposal that's made without that information is almost certain to be sub-optimal.
I had Energy Vanguard design a system for my new house build, and am now asking the same "Mitsubishi vs Daikin" question. Climate Zone3, winter temp 32/summer 91; heat load 28,200, cooling load 21,700. Mitsubishi recommendation of PUMY-P36NKMU1 with (2) ducted heads - the 18K PEFY-P18NMAU-E3, and the 12K PEFY-P12NMAU-E3 (along with about 60 feet of duct, priced out at $38K from the local certified Mitsubishi dealer. - more than I can afford. I don't have a firm Daikin quote in hand yet, but it will be a LOT lower.
Thoughts and advice? I know very little about Daikin except that it seems to have a pretty good reputation on some other pro/contractor forums...
Thanks,
Rob
Rob,
I did a very quick price comparison between Mitsubishi and Daikin equipment in the family of what you mention (36K ODU and 12K + 18K IDU). Where I looked didn't have the specific Mitsubishi SKUs you're referring to, but I picked the most expensive they had. The difference between Mitsubishi and Daikin equipment was about $2,500.
On a $38K quote, I'm not sure what constitutes "a lot" lower for you, but $2,500 wouldn't be enough for me to decide solely on price. Like you said, Daikin has a fine reputation, but I'm with Dana in that I want a product that lots of people are familiar with for when issues crop up down the line.
Patrick, this is a 2,500sf single story single family residence, new construction. The $38K number was a shock - it's actually more than the delivered cost of all the panelized walls and trusses combined! I will get other Mitsubishi quotes, but in the meantime another well-regarded local HVAC outfit will be quoting Daikin and I am expecting a significantly lower number based on 'back of the envelope' discussion so far.
I have heard nothing but good things about Mitsubishi, and I love their noise #'s; IMO HVAC should be neither seen nor heard if possible... hence ducted minisplits and good quality units. $2500 is enough to think about, but wouldn't be the determining factor; $10K, on the other hand...
To state my thought more explicitly, I just think you got a high bid and it's not necessarily the equipment choice that's the issue, so I agree with your approach to get some additional Mitsubishi quotes as well.
Maybe the S series equipment costs a lot more than m series. I see you have medium static units selected. I think Fujitsu might be worth looking at since you appear to have higher static pressure requirements based on your equipment selection. The Fujitsu units have stronger static pressure rating even in the low/mid static line than mitsubishi. Or, ask Energy Vanguard to rework the duct work design to stay within the cheaper m-series equipment with low static heads. If it's new construction it shouldn't be that big of deal to upsize the ductwork a bit to run at lower total pressures.
The P series Mitsubishi equipment appears to cost somewhere around $8-9K, whereas the M series is +/-$5,500-$6K for compressor and (2) ducted head units; the Daikin is priced comparably to the M series Mitsubishi. Seems like the $'s in my quote are 80% labor and ducting (all in the roof truss space with nothing in the way).
Rob, if you're doing new construction you'd be smart to consider having all of your duct work located inside the conditioned space of your house. Not only is the attic a very hot place to operate cooling equipment in the summer months, but any leakage in the duct work will result in an equal amount of air infiltration into your home, which increases your heating, cooling and de-humidifying loads, as well as reducing indoor air quality and potentially causing issues with long term durability.
Building a tight house with a properly implemented ventilation system and all duct work inside the conditioned space is the way to go if at all possible.
All of the ducts and air handlers are in conditioned space, Lance. Unvented roof, conditioned crawlspace, shooting for ~1-1.5 ACH. Not Passivhaus, but good enough... And we will probably only use the heating and cooling systems about 4 months of the year, we like open windows and doors and the climate (for a few more years, anyway) is conducive.
Good stuff!