Mini split ceiling cassette wall clearance

[makemenuconfig]

I'm installing a Fujitsu ceiling cassette unit in a bedroom, with the 3-way outlet configuration. The manual shows a min. 4" clearance, but then makes a note about ensuring sufficient service access. There is plenty of access from above in the attic.

Do you read that as the 4" clearance is required only to ensure access, or that 4" clearance is required no matter what?

I'm in a tight spot between trusses which can't be altered, and the otherwise ideal place to locate the unit leaves around 2.5" or 3" clearance to wall. Would you expect performance / comfort / airflow issues with this configuration, or do you think it will be fine?

 

[pcmeiners]

The access is is noted for installation, the lineset, drain line and 4 conductor cable. Just make sure you can get all these connected, after that clearance is not required .

 

[makemenuconfig]

That's what I was hoping. I just found different wording in a different document from them. I'm going to check the cleaning procedures and see if that yields any additional info.

"*When installing the indoor unit, be careful about the maintenance space."

 

[HassB]

@makemenuconfig, I assume you have already committed on the Fujitsu system but if not, just wanted to say I had the Mitsubishi (MLZ) Ceiling Cassette's installed in our bedrooms ~6 weeks ago and they work great and fit within 16" on center joists

Ceiling Cassette Mini-Split AC & Heating | Mitsubishi Electric HVAC US

Get a modern aesthetic and individual temperature control with a mini-split air conditioner and heating unit that recesses into your ceiling. Learn more.

www.mitsubishicomfort.com

 

[HamAndEggs]

@makemenuconfig, I assume you have already committed on the Fujitsu system but if not, just wanted to say I had the Mitsubishi (MLZ) Ceiling Cassette's installed in our bedrooms ~6 weeks ago and they work great and fit within 16" on center joists

Ceiling Cassette Mini-Split AC & Heating | Mitsubishi Electric HVAC US

Get a modern aesthetic and individual temperature control with a mini-split air conditioner and heating unit that recesses into your ceiling. Learn more.

www.mitsubishicomfort.com

Do you have pictures?

Any problems with clicking and creaking?

 

[HassB]

not yet, they have a built in pump and I have heard other pumps and this appears almost silent, they take a bit of effort to install, I had a company do them. see example images below, all the same room bar one as I wanted to show the view before the screen is on. Note they are one-way only

 

[makemenuconfig]

Yeah, I'm pretty committed to the Fujitsu. They were the only brand I could find which had the slim ducted style unit which could be mounted vertically. Plus, I've already ordered everything for it.

But I just called their tech support, and the support agent confirmed the only reason they call out that spacing is for access to the lineset and electrical connections, which in this application is a non-issue.

Here's a photo of the vertical unit if interested:

 

[HamAndEggs]

My mind cannot figure out where we are looking, are we looking up at the ceiling there?

 

[makemenuconfig]

No, this unit is mounted in a closet. Here's another angle for perspective. This isn't the one I was originally asking about, just sharing general progress.

 

[HamAndEggs]

Oh! Well that is pretty cool!

 

[Jackfre]

I’ve always tried to talk people out of the ceiling cassettes unless you have a lot of room for service. Simply getting it installed is the easy part. Cleaning becomes the challenge And it will need to be cleaned. I think for a single rom you are better with the concealed air handler installed in a closet ceiling serving that room. Also, depending upon the lay-out of your plumbing you may be able to avoid having to use a condensate pump. The Fujitsu pumps on the cassettes are able to pump up to 16” and then you have to have a gravity drain or another pump.

 

[makemenuconfig]

Well too late for me, I've already purchased all of the equipment. We considered a slim ducted unit, but once I framed the house, we decided the closet space we had was too small to give up. Wife was not willing to go for a wall mounted unit.

I've watched videos of how to clean the unit, and it doesn't look too bad. At least I know what I'm getting in for. And the condensate is no problem. I have plenty of room in the trusses and will route to a floor drain in the laundry. This unit can pump to 27".

 

[jlv03]

Oh! Well that is pretty cool!

It’s a heat pump. It can heat as well as cool!

 

[Gerald O]

If the ceiling space that it's going into is unconditioned space, like an attic, then you'll most likely need to thorougly insulate all around the cassette to prevent surface condensation. So plan for sufficient clearance for the insulation you'll add.

 

[HassB]

I think it depends which ones you use, the Mitsubishi ones are fully insulated sealed units, serviceable from below, but you can still cover them.

~6 weeks in the have been a winner in the bedrooms.

Thought I must admit one of them is very hard to get to from the top;