Any input on Mini Split A/C - Heat pumps?

[EricG]

I figure someone on here must have experience with these mini split units. My HVAC guy is recommending a higher end Fujitsu unit with 2 heads. My buddy (thermal engineer) is telling me Fujitsu is crap and I need to buy the high end Mitsubishi unit and I should use 3 heads.

I agree that using the 3 heads would be a perfect solution, but we only plan to use the unit a 2-3 weeks a year thus our HVAC guy suggested 2 higher output heads and leaving doors open on the 2nd floor.

The price difference between the HVAC Guys recommendation and my Freinds recommendation is ~$4k.

Thoughts?

 

[Coach13]

No personal experience but I have a friend that has a LG system. He swears it’s great.

 

[scott43]

2-3 weeks a year?? Well...ok...
My mom and dad invested in a unit for their house up north. Trane I believe. They chose to go 2 head heat pump for heating and cooling. They put one head on the main floor, one on the second. I'll say that house construction, sun exposure etc would have an influence. Their house is fairly modern so well insulated. Primarily it's to remove humidity and keep the temp comfortable in summer when very hot, so say 24-25C. Their house is about..I dunno..2500sq ft? Maybe 3000? Fairly open concept. Anyway, the rooms that are at the extreme other end of the house (they put the heads at one end of the house for convenience purposes) are somewhat warmer. Obviously it's not ducted. However, the house is extremely comfortable. More comfortable than my ancient house with no insulation in the city but with full ducted AC. They also have the advantage of being up in the bush where it does cool down probably 5C cooler at night than the city.

I believe they paid about $4k CDN for the entire setup. For them, being elderly, it was WELL worth the investment. I guess it depends on your expectations..some folks I know set their AC to 21C in the summertime which, to me, is extraordinarily wasteful and cold. We set ours to 25-26C and it's quite comfortable. They also set their houses to 24C in winter which, again, is pretty wasteful..

Oh..and I might trust the HVAC guys more..they install and service the units..they see real-world ops. I'm an engineer FYI..

 

[Jilly]

I had a Carrier system installed last fall. I'll have to get the spec's as I know nothing about any heads.....So far only used for heat, but summer is coming up. I have a 2 bedroom condo which is on the upper level. Think large one floor apartment with outside access. When I get back Sunday night I can check the spec's. There was an existing system which was over 20 years old.

 

[KingGrump]

Most of my HVAC subs like Fujitsu.
We have about eight Fujitsu units being used through out my family. No experience with Mitsubishi units.
Number of heads wise, we like more heads. Easier to balance the cooling requirements.

 

[EricG]

@Coach13 - I think LG is out fir us. The large supply house here dropped LG due to parts availability issues. So I’d have to go outa my way to get one.

@scott43 - We only ‘plan’ to use it for AC in the few weeks during August when it’s truly hot-humid. We can live without AC here, but it’s nice to sleep with the less humid air and work in a tad more comfort. Maybe we will end up using it more if it’s as effective & efficient as they claim.

Our house is well insulated and based on our energy/propane usage vs heat days put us in the top quartile in the VT energy surveys the past few years. It sounds like our usage would be similar to your folks, I’m just trying to keep it simple.

It is only an extra grand or so to have a unit with AC & heat vs just AC so we figured it would be a possible heat backup. I’m struggling with the cost difference of ~$7k vs almost $11k for a brand difference with similar specs.

@Jilly - is be curious to see which one. Carrier name has not come up yet in conversation.

@KingGrump - that’s good to hear. I’ve only heard positive info, but my buddy got me curious/nervous. I agree the more heads would yield more control. I wonder if I should revisit the 3 head idea.

 

[T-Square]

I’ve heard that the Mitsubishi mini-splits are pretty good. Number of wall units (heads) depends on house layout and size of each unit. You might want to talk to a engineer for the layout vs a contractor. You pay the engineer for his professional opinion and he should have no stake in the game for the manufacturer. His design for the system should take into account the insulation and home layout. A contractor may have a stake in the game for the manufacturer and may not have a good design background.

Full disclosure; I’m a retired Professional Civil Engineer (40 years) and specialized in Building and Home Inspection for 20 years. I’ve seen a bunch of these in the past 10 years. Most are pretty good and work well.

 

[EricG]

@T-Square - that’s kinda my issue. I trust my buddy, he knows my house but he’s known for over spec’ing everything. He likes everything set up for perfection, but budget doesn’t enter as a consideration. He can be very brand biased, which has always issue an issue when we travel together or just do home improvement projects. I noticed I mistyped in my first post, he suggested 4 heads not 3 as I wrote.

My HVAC guy has done a lot of work for us at our condo we bought & gutted along with a few smaller things around our regular house. He actually sent out a separate guy to review and spec the mini split units (I dont know his qualifications though).

 

[T-Square]

@EBG18T

Got to watch "over speclng" with AC. Actually slightly under sized is better than too large. A larger unit will short cycle which results in more wear and tear. A smaller unit running longer will get more moisture out of the air which is what you want. Around here we figure 15 to 20 BTUH per square foot. I’d tend to go with the smaller number. It may not cover you completely on a super hot day, but around here those are few. As long as it is cooler inside and you’ve knocked out the humidity you will probably be ok with it.

Hope this helps.

 

[John O]

We installed a Mitsubishi setup with 2 head units primarily for AC (we already have gas forced air heat, but didn't install central AC because our ductwork wasn't set up properly for cooling).

We've been very happy with it, but you need to have the appropriate expectations. Given that you're considering 2 vs 3 heads, what I will say is that we've found that without a very open floor plan, they really only do a great job of regulating temperature in the room they're in. So if you want the temperature in the location of that 3rd potential head to be consistent with the other locations, you actually do want the 3rd head. We run the fan on our furnace intermittently while using them to help circulate air, but there's still a very noticeable temperature gradient as you move away from the head units. It's just myself and my wife, and we put the 2 head units in the 2 rooms we spend the most time in, so our setup ends up working very well for us. But it's not as consistent and uniform as a central system, noticeably so.

 

[Jilly]

Invoice was still on my laptop.....Heat Pump is model 25HHA4. I went with Carrier because of the dealer. They had their office next door to mine office for 30 years. So I got to know the guys. I trust them. Also the Ontario government had rebates available for certain items, one of which was replacing an old heat pump. So, I also got a new electric furnace and fan coil. Installed around $6000.00

For some reason the residential part of their site is not working for me. So, no pictures or spec's at the moment.

 

[BS Slarver]

Many a Mitsubishi minis installed in our builds and they are yet to need anything but the occasional service.
Similar conditions that they are.month-ish users in the mountains

 

[EricG]

Many a Mitsubishi minis installed in our builds and they are yet to need anything but the occasional service.
Similar conditions that they are.month-ish users in the mountains

Sounds like you guys have had great experience with Mitsu, but any feedback on Fujitsu?

 

[T-Square]

Sounds like you guys have had great experience with Mitsu, but any feedback on Fujitsu?

Hmmm, crickets.


Kinda answers the question, doesn’t it.

 

[EricG]

Hmmm, crickets.


Kinda answers the question, doesn’t it.

Not nessisarily given the small population here. I have another contractor coming tomorrow that does Mitsu & Carrier. I’ll see what he has to say. The Mitsu distributor up here is smaller so I’m not sure how the pricing will look. I’m also trying to see which models they recommend versus what has a state efficiency rebate available. The rebates only $500, but it’s still $500.