Although most mini split indoor units are wall-mounted, for a more seamless look you may opt for a ceiling cassette.
Ceiling cassettes are installed into the ceiling where the mechanics are hidden. They cover larger areas than wall-mounted units, and in some cases, allow you to control the direction of air flow.
Ceiling cassette units come in different styles and boast interesting features to meet the needs of various applications.
When to Choose a Ceiling Cassette Unit
Ceiling cassettes are discrete units that hide the bulk of the unit above the ceiling. The grille, which is approximately 1" thick, is all that shows. So if you're looking for a less noticeable unit that offers improved coverage, this may be what you're after.
If you have a large room with hot or cold spots, a ceiling cassette can fix that. They have four outlets that blow air - one on each side. Some models offer the option of closing one or two vents if you have a direction you'd rather not blow air.
This comes in handy in a hallway where you might only want to direct airflow in two directions. If you install it near a wall in your living space, and you only want to direct air in three directions, you can close one vent so you're not blowing directly at that wall.
Ceiling cassettes fit well in drop ceilings, but because of their size, you'll need to make sure they will fit into your attic above the space you wish to condition.
Ceiling cassette units operate best when they're installed in the center of a ceiling. This is because they have four vents directing air in four different directions.
If, for some reason, you're unable to install the unit in the center of your ceiling, close off any vents that are aimed directly at a wall.
It's also important to know how the ceiling cassette will fit into the designated space. The dimensions of the units themselves start around 24 by 24 inches (like a ceiling tile). If you're planning an installation between rafters that are typically 16 inches apart, then customization will be needed in order to make it fit.
These units come with a built-in lift pump for removing condensate that's created by the cooling process. The lift pump gets connected to 1" - 1.25" rigid PVC piping that runs to the outside of your home.
Because your ceiling cassette unit must be installed above your ceiling, it has to be suspended with rods or cables from the structure above it. You'll need at least 10"-12" of available space above your ceiling to fit the unit.
If you're installing the unit in an unconditioned space, such as an attic, you must insulate it. Running a ceiling cassette unit in an unconditioned space without insulation will cause condensation to build on the outside of the unit and drip into your living space.
The units themselves have built-in thermostats for reading indoor temperature and adjusting their output accordingly. Being in an area that's warmer or colder than the rest of the room will cause it to inaccurately condition your living space.
Other Features of Ceiling Cassette Units
Ceiling cassette units don't boast as many features as wall mounted units, but they've got a few options for different applications.
Many of the features depend upon the brand or model you choose, so be sure to consider what features you need when searching for a unit that's right for your application.
If you're installing a ceiling cassette unit in a large family room, but would also like to condition a separate den that's adjacent to that family room, you may not need a separate unit.
Some ceiling cassette models will support the use of a branch duct to move some of the conditioned air to that space, conditioning the family room and the den from one unit.
Many units are capable of being connected to a fresh air intake. This means that instead of continuously recycling the same air in your home, you can draw in, condition, and cycle fresh air throughout your home.
In terms of temperature control, you can opt for either a wireless remote control or a wired-in wall mounted control. This also depends upon the make and model of the ceiling cassette unit.