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Are mini split ceiling cassettes an option without access from above the cassettes?

I'd like to have an HVAC contractor install a Mitsubishi mini split system that would include two ceiling cassettes that do not have access from above where the cassettes would be mounted. I know the annual cleaning is done from beneath the cassette. But at some point in the future if a condensate pump goes bad or the cassette needs a major repair or replacement, is it possible to service these cassettes without access from above? Could it be installed so the entire cassette could be lowered somewhat below the ceiling for the repair? Could the lineset and condensate drain be set up with enough flex and extra length to drop the cassette a bit down from the ceiling for future repairs or replacement? The HVAC contractor who visited the project site said he doesn't like ceiling cassettes, no way no how. He did not make it clear whether this is just a personal bias on his part, or if installation without access from above makes it impossible to use ceiling cassettes. He wants me to buy the ugly wall-hung heads, or go with a full ducted system -- both of which options do not interest me. Thoughts? Is the lack of access from above the cassettes a deal-breaker?

Comments

  • mattmia2
    mattmia2 Member Posts: 10,952
    Sounds like you may need a new installer. There are also ducted min splits that can be concealed somewhere where they are serviceable.
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,488
    What type of ceiling are you mounting them in?

    If there is no ceiling access, how do you expect they can be installed?

    Most of the cassettes I have looked at have limited condensate head pumping ability.

    Is this an existing ceiling/house or new construction?
  • ratio
    ratio Member Posts: 3,791
    If you had an access panel in the right spot it might be ok.
  • wesPA
    wesPA Member Posts: 38
    Check out the Mitsubishi MLZ series. Designed to fit between 16" joists.  All components can be accessed from the ceiling opening by taking off the grille, including the flare nuts and pump. Just roughed in my first one last week, so don't have any operational feedback yet, but overall was impressed with the unit
  • pecmsg
    pecmsg Member Posts: 5,297
    Ceiling cassettes use a condensate pump that many people complain about the noise. Mostly from bedroom installations. 
  • Motorapido
    Motorapido Member Posts: 314

    What type of ceiling are you mounting them in?

    If there is no ceiling access, how do you expect they can be installed?

    Most of the cassettes I have looked at have limited condensate head pumping ability.

    Is this an existing ceiling/house or new construction?

    This is the upstairs, which until our renovations had a ceiling consisting of the sloped roof rafters, with OSB nailed to the rafters. Now, I have finished the ceiling in pine tongue and groove boards, and created a flat, dropped ceiling about 4 1/2 feet wide, dropped about 20 inches from the ridge rafter. That flat ceiling will also be clad with pine boards, and the flat ceiling will contain several 6 inch wafer LED lights, two ceiling fans, and serves as a chase through which some Romex runs from end to end. The cassettes would go into this small dropped ceiling. The only way to gain access from the top for future service would be to create access hatches by cutting open the roof -- so obviously not an option there.

    If I'm reading the specs correctly, this proposed Mitsubishi cassette installation would make for less convenient access for future repairs, but would not make future repairs impossible, right? It appears that all the guts of the cassette can be cleaned, serviced, repaired or swapped out from below. If that is correct, for the sake of aesthetics, it's worth the trade-off to me to create inconvenient future service access for the benefit of not having to install what I consider to be ugly wall-hung condenser/blower heads. I just want to make sure I'm not creating an impossible-to-service scenario.
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,488
    I would stick with the wall mounts
  • ratio
    ratio Member Posts: 3,791
    I despise the wall tumors, there's nothing uglier than them.

    If the paperworks say it can be serviced 100% from below, you should be ok—I'd complete the lineset pressure test prior to closing it up.

    Alternately, you should be able to fabricate a removable panel for that ceiling with nothing more obvious than the edge cuts of the panel itself.

  • offdutytech
    offdutytech Member Posts: 161
    From a service standpoint I'm not a fan. It's not always possible or desired to go with a wall mount. Here is a job we are in the process of installing a ceiling mounted unit at. It's in a third floor attic build out so space was limited. 
    Motorapido