Split Air Conditioners. A.K.A, Ductless Air Conditioners

Split air conditioners are also known as ductless air conditioners. If you ask me, I would categorise ductless air conditioners as the final evolution before central air conditioners.

Split/Ductless air conditioners are designed with super comfort silence in mind, whilst providing you the comfort air you need.

Let’s learn more about split air conditioners.

Overview of split air conditioners:

Air conditioning principle for ductless air conditioners, are based on refrigerant compression and expansion, a.k.a. mechanical cycle air conditioning.

The size range of these air conditioners is from,

  • 5,000 BTU/hr (or 0.43 ton or 1.4 kWh or 1.1 hp), to

  • 50,000 BTU/hr (or 4 ton or 13 kWh or 10 hp)

With efficiency ratings from,

  • 9.5 SEER, to

  • 19 SEER

Split air conditioners are designed to condition air from small rooms, to large rooms.

Efficiency ratings for these air conditioners are similar to window units.

Design features:

  • Split air conditioners are constructed in two parts.

    One part is the condensing unit, where the compressor and the condenser coil will be placed.

    The other part is the evaporating unit, where the evaporator coil will be placed.

    Condensing unit will be placed outside of a conditioned building, and the counterpart will be placed inside.

    You know what this means. Super quiet, comfort air!

    No more noise from the compressor into the conditioned space

  • The separate construction also allows for use of several evaporator units, for one condenser unit.

    Hence, you can condition separate spaces, with only one condensing unit.

    However, this shall not be modified by the user. Manufacturers of ductless air conditioners will provide those as a package

  • Copper tubing will be connected from the condensing unit, to the evaporating unit during installation at site.

    Copper tubes will be connected through tube soldering

  • There must be a properly installed condensate drain from the evaporating unit, to the nearest drain

  • Similar to window air conditioners and portable air conditioners, most ductless air conditioners are equipped with dehumidifier only function.

    This function is achieved by


    Passed through the evaporator for water condensation, and heated for dry air


    Passed through the evaporator, at very low blower speed and lower temperature.

    Blower speeds during this type dehumidifying action, is fixed to control the moisture removal.

    A high blower speed will not remove moisture effectively as water vapour will be carried together with the blowing wind

  • Most split air conditioners come with a heat pump function as well. So, you can use the air conditioning unit throughout the year

  • An excellent feature, most split air conditioners come with, is the activated carbon cartridge, as an integral of air filtering.

    What is so good about this cartridge? It removes odour.

  • Here comes the ”wow-factor” part.

    Recently, ductless air conditioner manufacturers have come up with a new technology to clean the filters.

    That cleaning action is achieved by an automatically moving brush within the air filter frame

  • Ductless air conditioners are equipped with auto swing flaps to direct air flow into a larger area within the conditioned space

  • These units are installed higher than window air conditioners, and hence remote control is a necessity

  • All split air conditioners comes with digital control

  • Safety must be an integral part of any air conditioner design, and hence magnetic starters are very important for a proper and safe operation of split air conditioners

User profile:

Ductless, or split air conditioners will be very useful if,

  • You want a very quiet air conditioning unit,

  • You want to install air conditioner at several uncomfortable rooms only,

  • You want to install a conditioning unit to a large room that is very seldom used,

  • You are running a resort business, and you need air conditioning to all rooms

Installation and setup:

Installation and setup for these air conditioners are a bit more difficult than window air conditioners.

You have to first, size the air conditioner, purchase it, followed by,

  1. Identify the spot to install the evaporating unit,

  2. Drill holes for refrigerant lines and condensate lines,

  3. Install brackets for the evaporating unit,

  4. Install brackets or floor bolts, and install the condenser unit,

  5. Install tubing and condensate lines,

  6. Mount the evaporating unit on the evaporator bracket,

  7. Fit the condensate and refrigerant lines,

  8. Wire the system,

  9. Evacuate the system, test for leaks, check for moisture, and charge adequately.

    These activities are mentioned in detail here

Service and maintenance:

For split air conditioners are similar to steps mentioned in air conditioning maintenance page.

Pros and cons for ductless or split air conditioners:

CostLow maintenance costHigher operating cost, due to lower EER compared to a portable, or central system
Air qualityGood, if the filter is maintained. Odour removal comes as a package with most air conditionersNot as good as central air conditioners, as air is re circulated. A small provision for fresh air will be good
MobilityNoneHave to do proper removal before moving this unit
Conditioning abilityLarger units (cassette, or inverter construction) may condition a space up to 4,000 square feet of floor areaNone
NoiseVery quietCentral air conditioners are better
Stylish lookSleek designCentral air conditioners are better
StrengthGood installation strength. RobustNone

Is it the best system for you?

Split air conditioners are best used for zone based air conditioning, where low noise is a requirement and odour control is importance.

Plus, you get to enjoy the design and admire… on the technology behind the beautiful machine.

Top of Ductless or Split Air Conditioners page

footer for air conditioner page