Mitsubishi Zuba vs Trane XV19
Hi,
I have benefitted immensely from the questions and thoughtful answers on this forum. It has been one of the few places where I can get answers about HVAC questions that are based on fact. I am posting this here to help others behind me in terms of costs and perhaps to get some shared wisdom on picking a system.
Most of the HVAC companies I have contacted about replacing our entire HVAC system in a major renovations have offered quotes without even coming to look at the house, preferring instead to use rough calculations of square footage per ton. This seems crazy since we’re rebuilding a 70 year old house with much higher insulation.
Located near Montreal, Quebec, (Zone 7?) the rebuilt house will have R30 walls and R60 attic insulation with triple pane windows. The house is 4200 sq/ft, 3400 sq/ft on the main and upper floor.
We have two good quotes (mini splits are out of consideration because of the unique requirements of a 8′ x 16′ window in the kitchen (and my wife doesn’t like the look):
1. Trane XV19 4 ton, with a heating coil pack of 25KW in the TAM9 communicating 5 stage air handler. Includes a Fantech 250CFM HRV with a hybrid installation (exhausts in bathrooms and fresh air venting into main heating ducts), fancy Trane thermostats, two zones (upstairs and main floor) and all new ductwork. Cuts out at -25 C. Total cost: $36,375.
2. Mitsubishi Zuba: 3.5 ton, with a heating coil of 17KW in the PVA-A42AA air handler unit. Includes a Renewair E200 ERV also with a hybrid installation (exhausts in bathrooms and fresh air venting into main heating ducts), Honeywell MHk1 thermostat and all new two zone ducts. (NB: they are creating two zones but it is manual, for now as they tell me that Mitsubishi is coming out with their own zoning system in the next year which I could upgrade to if I wanted). Cuts out at -30 C. Total cost $35,175.
I had a whole house heat loss calculation done and these sizes appear in line with that result.
My question for you is: which system would you go for? Price is basically the same. They are both probably pretty good and they both seem like really good contractors, unlike the six others I spoke to first who were awful.
1. I don’t really understand or have the figures regarding range of modulation for each system so maybe one will be more efficient/comfortable than the other within my climate?
2. I haven’t seen anything on this site about XV19 but it seems like a good system. If you have such a system, could you please share your thoughts? Anyone else consider it and dismiss? How does it stack up to the Zuba?
3. The Mitsubishi only modulates on a single zone at present and I didn’t want aftermarket zoning dampers that wouldn’t work well, but having an upstairs and downstairs zone seems to me like a pretty good idea. The Trane equipment is all Trane and communicates with each other. Is this just a sales pitch or is that going to make the house more comfortable and efficient?
4. I believe both will interlock the HRV/ERV to the air handler. The Trane system will have boost in the bathrooms to get the HRV to clear the mirror. The Mitsubishi guy is adamant that this won’t work and that we should put in bathroom fans to supplement. I think his ERV he spec’d isn’t an ECM motor but rather runs at one speed. The first one sounds good but also sounds more complicated to commission. The second ERV system with Mitsubishi sounds easier to commission. What are your thoughts?
Thanks so much in advance for your consideration,
Josh T.
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Replies
Hi Josh,
What is your actually calculated heat load? The units seem at least a bit oversized if I use my house as a reference. I'm in Gatineau, zone 6 as well, with a house that is less well insulated and my heat load from gas use is at about 34 000 btu for a 4000 square feet house, 2700 on the main and upper floors. I have half my windows as triple pane and one wall insulated to R30. I would expect your house to be below mine in heat requirement.
I know it must have been a headache to come up with a plan that seems all set to be put in action, but I would look at ducted mini splits if you are willing to explore other options. They modulate a lot more than the central heat pumps you're looking into, which would make them more comfortable especially in shoulder seasons. They probably will not be more expensive than your current quotes. Is the total cost before or after taxes?
Do you have the actual model number of both units? I get more than 300 hits on the XV19 on neep's website. They all have pretty minimal modulation, but it would be helpful to know which one to look for.
If you have the budget for it, I would definitely pay for separate ducting for the air exchanger. Do you have a blower door test result to share?
What Fantech series are they installing with the Trane? I'm not as familiar with the Renewair models.
Hi,
Thanks for your note. For a variety of reasons owing to the design and layout of the house, mini splits aren't an option. The XV19 model number is 4TWL9048A1000A (4ton) and the air handler is TAM9AOC48V41DA (5 stages with 25kw heater). According to installer this unit modulates from 25-100% (but I don't know at what temperature).
No blower door test (and not relevant since the house is currently ripped down to bare brick).
I don't know the modulation of the Mitsubishi unit either. Of note, the Quebec government gives a higher rebate to Mitsubishi over the Trane unit (and that is based on BTU output at -8C), meaning that even though the Mitsu is a smaller output unit, it is putting out more heat at -8C than Trane. Interesting...
Fantech Hero 250 is the model. Thanks!
Trane doesn't make it easy to find their models of the neep website, they have over 100 configurations of the 4TWL9048A1...anyway I digress...
What was your heating load at 99%?
I'm asking as the unit's output drops significantly with colder weather. You lose 20% capacity by -15C just when you need it most whereas the best cold weather units lose less than 10%.
According to neep's data, I'm not sure the modulation is really a selling point. I can't find more data from Trane.
It does modulate, but the max output goes up by a large amount with increasing temperature. So at -8, the minimum output (24 000 btu) is already way above your heating needs, same at 8 degrees (17 000 btu min.). Even if it modulates then, it will operate like a one stage unit.
It might not matter much to you though, it's really a question of preference and it depends on what was your previous heating system. If you're used to a one stage unit and found it fine, just your increased insulation and the small amount of modulation in cold/very cold temps will do the trick. I'm sure you can find better for the money you're spending though.
You said your design does not allow for mini splits. I'm assuming you are referring to ductless heads, as I don't see how you could accomodate a centrally ducted heat pump, but not a slim or mid static unit. Have you looked into the fujitsu/mitsubishi/carrier/midea slim ducted units at all?
Their output holds up better in colder weather and they have much better modulation.
As an example, a 2 ton carrier 40MBDQ24 has a max output of 24 000 btu at -15C, almost same as you 4 ton unit, but a min of 6 000 btu at -8 and 8 C with a maximum of about 26 000 at those temperatures. It would run much longer in all seasons and probably be quieter as well.(https://ashp.neep.org/#!/product/26450).
If ever you're interested, neep's website is a gold mine : http://ashp.neep.org/
Curious to know who you spoke to at Mitsubishi about them coming out with a zoning system. I am in Ontario and am looking to install a similar system. I just received my quote for a Daikin system $40-43k. The Daikin life can support multiple zones but is not as good in the good as their Daikin Aurora or Mitsubishi Zuba hyper heat.
PS. Check out Vanee for your ERV (if you want an ERV) they are self balancing. Or Renewaire EV Premium M or L
Hi,
The installer spoke to someone at Mitsubishi Canada and he relayed this to me. It was in response to my question for having two zones (one upstairs, one downstairs). That's all I know about it and I would buy Mitsubishi unit set up for manual zoning, with the possibility of retrofitting later.
As for ERV, why upgrade to Renewaire EV Premium? I know it has an ECM motor but is this attractive for energy savings? The EV200 is right size for my house and I kind of like it's 'on or off' as it will make commissioning and balancing easier. I will have Panasonic bath fans installed so I don't need a boost function or anything out of the ERV or anything fancy. Am I missing anything?
BTW the energy penalty for operating the EV200 vs the EV Premium M (roughly the same size) is less than 40 watts - so negligible. Thanks!
I was really interested in the Trane XV19 when I was researching. I found out that it’s a Mitsubishi City outdoor unit, designed to be small and extremely quiet. Trane/Mitsubishi partnership. It modulates from 25% to 100% which is very good for a central style system. The SEER and especially Hspf look really good. The HVAC company has to be a Trane Gold or Platinum or something, dealer to even offer them, my local dealer didn’t know what it was, hadn’t seen one, but that was almost 3 years ago.
Thanks David,
For me, your answer captures exactly my trepidation: sounds like you too were interested but didn't buy it... Who has? I haven't seen anything...
The performance specs were very good, and Trane listed it as a Value for a variable system. I just couldn’t even get a quote from the one Trane dealer qualified to offer it.
I don't have any specific comment on Trane vs. Mitsubishi... I just wanted to share my experience with Trane zoning. I have the XV18 heat pump & TAM9 air handler with the Trane zoning system, and it is outstanding. Vastly exceeded expectations. I have 4 zones (three zones on the 2nd floor of my house, one zone on the 3rd floor), and it easily maintains all of them to within 1 degree of the setpoint, even if the setpoints are different by 3 or 4 degrees. For example, attic setpoint 78, master bedroom 73, and secondary bedrooms 75? Yep, keeps them all within 1 degree of the setpoint. And often it's even better than 1 degree. For example, in the winter when we have a relatively consistent load... say, it stays 30 degrees more or less all night long. It will actually keep all 4 of the zones within about 0.2 degrees. I might have secondary bedrooms set at 68, and they will stay between 67.7 and 67.9 all night long. (Note: Temperatures measured with SensorPush sensors, so I think they are reasonably accurate.)
So yeah, I can't speak to Mitsubishi zoning, but I've been incredibly impressed with Trane's zoning.
If you look at the cost of the accessories needed for zoning you get pretty close to the cost of a 2nd heat pump.
Besides redundancy, this means no ducting through the main floor and very short return ducts. Well sealed short returns with a quality filter mean pristine air handler and ducts for many years.
I got quoted between $3500 to $4000 Canadian, depending on brand, for a ducted 1.5 ton hyper heat system (these are the slim style, they work for one story layout well). Ductwork is extra, but still nowhere near to justify a $35k to $45k price tag.
What I find works best is to have the ducting and the unit install quoted separately. This will get you much closer to time+materials bid. Just make sure somebody, not your HVAC guy, designs the ducting beforehand.
Fantech units are pretty mid grade and the EV200 is pretty much in the same ballpark. Since this is something that will be running 24/7, you want a unit with ECM blowers and in cold climate it is worth while to pay extra for a higher efficiency unit. I would look at either a Panasonic Intellibalance/VanEE G2400E/Zehnder CA350ERV. The CA350ERV unit by itself is not expensive if you can skip their ducting system.
Akos, do you know a good company that does duct designs in Quebec/Ontario?
It seems like they don’t want to be found.
You try contacting one of the posters here:
https://www.greenbuildingadvisor.com/profile/Yupster
Akos,
Informative post. Totally, agree having two heat pumps with dedicated outdoor units is a superior option as they modulate better and as you mentioned less duct work. In Ontario, it is required by building code to have a designed heating and cooling system that includes the ductwork layout.
The problem I have encounter slim ducted heat pumps are as follows; Installation in a second floor ceiling. To do so requires plenum truss's or interior ceiling bulk heads as well as a large access hatch. Otherwise, you need to install these indoor units in a closet that eats up valuable square footage. In addition, you would require completely separate ductwork for your ERV/ HRV. Whereas, if you have one central unit you can tie your ERV/ HRV into your existing return duct work ala "exhaust ducted system" https://www.greenbuildingadvisor.com/article/ducting-hrvs-and-ervs.
One last thing to note in Ontario Canada regarding HRV/ ERV's. Just because a unit is tested and listed on the HVI website (https://www.hvi.org) doesn’t mean it meets the Ontario building code (OBC) requirements.
In Ontario, you have two targets for ERV/HRV: one at -25°C and at 64 cfm minimum, the HRV/ERV must have an SRE above 55% - that is a Part 9 OBC target. AND to meet your specific EEDS / SB-12 target, it must also be above 55% SRE at 0°C and 64 cfm. If you look at the only Zehnder ERV on the HVI website, you can see it's not rated at -25°C, so it can't be used as the first target is not being met. (Probably doesn’t go into defrost). Long story short Zehnder is cool but not up t0o OBC. Vanee, Panasonic, Renewair more ideal.
I'm currently installing a Midea mid static unit that can be mounted vertically. It takes up 3'x1' floor space including intake filter. There are some bulkheads for the supply ducting, but there are almost always bulkheads for those and since it is on the 3rd floor with bedrooms, it doesn't matter much unlike a living space. I would call that a pretty small space loss vs a central option, you are probably loosing at least 3x that much floor area to run up to a 3rd story .
For ERV ducting, to me, the best shared duct setup is a hybrid connection, that is run only the fresh air supply to the intake of the air handler. It doesn't matter how many air handlers you have, run one appropriately sized feed to each. This also means the air handler doesn't need to be interlocked with the ERV, when the unit is off, the return ductwork supplies the house. The stale air pickups still need to be ducted which does add a bit of extra cost.
Regarding ducting, the hybrid connection is what I have settled on too. Stale air ducts out of all the bathrooms and fresh air ventilated throughout the house via the main duct system. I think this will work properly so long as you don't try and get too fancy (ie., boost function in bathrooms).
Besides, the Zuba air handler basically runs all the time anyway.
I would run a largish stale air pickup (65cfm) to your kitchen area. This should be kitty corner from your stove, about 8' away. Cooking is the largest source of indoor air pollution, range hoods help but don't eliminate it. You want a way to clear these without distributing it through the house.
You do want a boost switch and it should be in your kitchen and in any bathrooms that ERV is connected to. It doesn't matter much if boost unbalances your ERV as it only runs for shortish time. With a good install and properly sized ducting it should not be an issue though. Boost function should work in a hybrid connection setup as well.
"If you look at the cost of the accessories needed for zoning you get pretty close to the cost of a 2nd heat pump."
For me, when we were finishing my third story attic, adding zoning to our existing Trane system was about $2000. This came with the benefit of not only providing heating/cooling to our third floor, but also adding individual temperature control over our master bedroom, secondary bedrooms, and bonus rooms on the 2nd floor. Before we had zoning, the temperature differential in these second story rooms could be as high as 3-4 degrees -- not because of poor duct work, but because some of the rooms have south facing walls and get blasted by the sun all day, whereas other rooms get essentially zero direct sun.
If we had done a ductless mini split in the third floor attic instead of simply zoning our second floor system, it would have cost about $5,000, and would not have solved the temperature differential problem on the second floor the way that the zoning system did.
Anyways, the purpose of my post is merely to say that there are situations--perhaps rare-- where zoning, rather than a second system, can both be noticeably less expensive AND provide enhanced overall comfort. But yes, with zoning you'd always lose the redundancy that a second system provides.
Thanks for the advice, very helpful. The energy penalty for the EV200 is less than 40 watts compared to a similar unit with an ECM motor so I don't know how much this is a concern. More so is that the Renewair Premium EV (with ECM motor) is new as of last year. Not too keen on installing something new where they are working out the kinks still when the potential savings in energy is so minor. Panasonic Intellibalance is interesting but don't you have to install several?
Thanks!
Power costs for anything that is running 24/7 quickly adds up.
The EV200 shows the power consumption at 150W, an equivalent ECM unit is around 80W. Since it is running 24/7, at my power cost of $0.15, that works out to $90/year. The ROI is pretty short for a better motor.
PSC motors also don't turn down well, at half flow rate, the motor still consumes close to rated power an ECM blower drops down to around 1/3.
ECM blowers also tend to have much steeper pressure/flow curves making them much less sensitive to external static pressure changes. This is important for a unit connected to an air handler.
A better unit is almost always worth it.
Thanks Akos, this is great advice. I've asked the quote be revised to include the Renewaire EV Premium M and to add boost buttons in the bathrooms and kitchen.
Once I get this new quote, I'm going to pull the trigger on the Mitsubishi unit. It is going to be great.
Thanks so much all for the thoughtful advice. Hope this threat helps others who come after me!
Can you give us an update once the installation is complete? We seldom hear of the outcome of a given project.
Hi, wanted to give a quick update (without much new info). I upsized the ERV to the Renewaire EV Premium L. Construction is ongoing. The equipment is in but not commissioned yet.
Not surprisingly, everything has taken forever as a result of supply chain problems.
One thing I regret is not having an engineering company design the HVAC system first. The guys doing the install know what they are doing and they were fastidious, but if I could do it again, I'd have an engineer design it.
That's it for now. I'll let you know when it's up and running!
Hi Tanton, I'm also from Montreal (south shore), I came accross your post when googling these 2 heatpumps, the zuba was suggested by the company that gave me a quote to replace my current system which is 14 years old (the quote is 15 000$ for 42 000 btu, model is PUZHA42NHA5). How do you like yours in the end ? On Trane's website, they say the XV19 goes as low as 43 db I think, which is quite lower than the Zuba (49db I think) but I don't know any company selling them in my area and Zuba selling point seems to be that it's eligible for the new federal credit via RénoClimat.
I have replaced two Trane Thermostats since 2018 —use an Ecobee or something more reliable. The TAM9 units are quiet.
Unfortunately for Trane's modulating equipment, I'm pretty certain you are required to use Trane's thermostats or you don't get modulation.