Plenty of Long Island houses were never built for central air. A Cape with hot water baseboard has no ducts to blow cold air through, and the finished room over the garage was added long after the boiler was sized. Those are the houses where a ductless system usually comes up.
A mini split is a small heat pump. PSEG Long Island describes it as heat pump technology that provides cooling and heating without installing ductwork. An outdoor unit connects through a small hole in the wall to one or more heads mounted inside, and each head can be set to its own temperature.
Rooms where ductless makes the most sense
All Island Comfort lists the jobs it installs mini splits for most:
- Capes and ranches with baseboard heat and no ducts
- additions the existing system does not reach
- bedrooms over the garage
- garages and workshops
- sunrooms and three-season rooms
- finished basements and bonus rooms
- upstairs rooms that run hot or cold
- home offices that need their own zone
- room-by-room replacement of window AC units
- whole-home heating and cooling without ducts
Single zone or multi-zone
A single-zone system is one outdoor unit and one indoor head. A multi-zone system runs several heads off one outdoor unit. All Island Comfort says most single-zone installs are done in a day and multi-zone systems take 1 to 2 days, depending on how many heads and how the lines are routed.
All Island Comfort lists what moves a mini split quote:
- the number of zones
- the style of each indoor head
- standard or cold-climate equipment
- the brand (it installs Mitsubishi Electric, Daikin, Fujitsu, LG, Samsung, Carrier, Bosch, Trane, Lennox, Bryant, Gree and York)
- line-set length and how hard the routing is
- electrical work
- condensate pumps, which may be needed in basements or for heads on interior walls
- permits
Their multi-zone range is about $8,000 to $18,000 installed. They do not quote single-zone prices off a sheet over the phone.
Cold-climate models and January
Ask for a cold-climate model if the mini split will heat, not just cool. All Island Comfort says cold-climate models hold rated heating capacity down to about -5°F, and names Mitsubishi’s H2i line and Fujitsu’s XLTH line as built for that duty. The NEEP cold-climate listing that PSEG relies on applies to ductless systems as well as ducted ones, so you can check a mini split model the same way you would a central heat pump.
The rebate question for one room
PSEG Long Island’s 2026 single-family rebate covers whole-house projects only: the heat pump system must meet 100 to 120% of the entire home’s heating load, with a Manual J to prove it. PSEG’s January 2025 program announcement discontinued the old $250 per heat pump equipment-only rebate.
One head in one bedroom does not qualify. A ductless system designed to heat the whole house can, if it meets the same conditions as any other whole-house heat pump. The heat pump page and the rebate guide have those conditions.
Care that keeps a mini split running
All Island Comfort’s maintenance advice:
- rinse the washable filters in each head every 2 to 4 weeks during heavy summer and winter use
- have a technician clean the blower wheel, coil and drain pan once a year
- near the shore, ask about more frequent rinses of the outdoor coil for salt buildup
If an indoor head drips onto a wall or floor, turn it off until someone looks at it. All Island Comfort says the fix is usually a flushed condensate line, a clean drain pan and a check of the line’s slope.