Central AC vs. Ductless Mini-Split: Which Is Right for Your Home?

Two main options dominate residential cooling in southern New Hampshire: central air conditioning (a single outdoor unit paired with an indoor coil that distributes cooled air through ductwork) or ductless mini splits (an outdoor unit paired with one or more indoor heads that condition specific rooms). Both work well; the right choice depends on your home's existing infrastructure, layout, budget, and comfort priorities.

Here is an honest comparison from a New Hampshire HVAC installer.

Central air conditioning

How it works

An outdoor condenser pairs with an indoor coil installed in or above the furnace or air handler. The blower pushes air across the indoor coil and distributes cooled air through the home's existing ductwork to supply registers in each room.

Where it fits best

• Homes that already have central forced-air heating (existing ductwork is already in place)
• Whole-home cooling from a single system
• Larger homes with multiple rooms to condition
• Homeowners who want temperature control from a single thermostat per zone

Pros

• Lowest install cost when ductwork already exists
• Whole-home coverage from one system
• Filtration, humidification, and IAQ equipment can be added to the duct system
• Familiar operation and thermostat interface
• Quiet outdoor unit can be located away from windows

Cons

• Significantly more expensive if ducts must be added (running ductwork through finished walls and ceilings is invasive and costly)
• Duct leakage can waste 20 to 40 percent of cooling capacity if the system is not well-sealed
• Single zone (or limited zoning with dampers) means temperature is averaged across the whole home
• Cycles on and off, which can produce temperature swings and uneven humidity removal

Ductless mini splits

How they work

An outdoor unit pairs with one or more indoor "heads" mounted on walls, ceilings, or floors. Refrigerant lines connect each head to the outdoor unit. Each head conditions the air in its own zone independently. Multi-zone systems can support 2 to 8 indoor heads on a single outdoor unit.

Where they fit best

• Homes without existing ductwork (most older NH homes with hydronic baseboard heat)
• Room additions, finished basements, sunrooms, three-season porches
• Specific rooms that the existing HVAC cannot cool well (master bedrooms, bonus rooms over garages)
• Homeowners who want zoned, room-by-room temperature control

Pros

• No ductwork required (no install invasiveness for finished homes)
• Zoned by design: each room or zone is independently controlled
• Highly efficient (no duct losses; variable-speed inverter compressors)
• Same equipment provides both cooling and heating (it is a heat pump)
• Operates very quietly indoors
• Variable-speed operation produces consistent temperatures and excellent humidity removal
• Choice of indoor head styles (wall, floor, ceiling cassette, concealed ducted) to fit room layouts

Cons

• Higher per-zone equipment cost than adding a register to existing ductwork
• Indoor heads are visible in the room (some homeowners object to the appearance)
• Multiple thermostats or remotes for multi-zone systems
• Wall, floor, or ceiling penetration required for each head's line set

How to choose

Question 1: Do you already have ductwork?

If yes: central AC is usually the cheaper install. Ducts are already in place; you just add the indoor coil and outdoor unit.

If no: ductless mini splits avoid the cost and disruption of adding ducts to a finished home.

Question 2: Do you want whole-home or specific rooms?

Whole-home: central AC or a multi-zone mini split system.

Specific rooms only: single-zone mini split heads in just the rooms that need conditioning.

Question 3: Do you also want heating?

Modern heat pumps (whether central or ductless) provide both heating and cooling from the same equipment. For NH homes ready to convert away from oil or propane, the heating side often makes the heat pump the right answer regardless of duct situation.

Question 4: How much do you value zoned control?

Mini splits are zoned by design. Central AC can be zoned with dampers and multiple thermostats, but the zoning is less granular than separate mini split heads.

A hybrid approach

Many NH homes end up with a combination: existing forced-air central AC for the main living areas, plus one or two mini split heads in problem rooms (the bonus room over the garage, the finished basement, the master bedroom that never gets cool enough). This often delivers better comfort than trying to force either system to do everything.

Cost comparison (rough)

• Central AC, existing ducts: $5,000 to $9,000 installed for a typical NH home
• Central AC, ducts needed: add $5,000 to $15,000+ for ductwork installation
• Ductless mini split, single zone: $4,500 to $7,500 installed for a typical NH room
• Ductless mini split, multi-zone (3-4 heads): typically $15,000 to $25,000 installed for a whole-home system

The federal 25C tax credit for heat pumps ended December 31, 2025. NHSaves utility rebates and financing remain available and can substantially reduce the out-of-pocket cost on either system; ask us for current amounts.

Schedule a consultation

If you are weighing central AC vs ductless for a NH home, contact A.J. LeBlanc Heating. We install both and will walk through which makes more sense for your specific home. Serving New Hampshire families since 1928.

Frequently Asked Questions

Which is more efficient, central AC or mini split?

Mini splits typically have higher rated efficiency (SEER2 18 to 30+) than central AC (SEER2 14 to 22). The gap is even larger in practice because mini splits have no duct losses.

Can I cool my whole house with mini splits?

Yes. Multi-zone mini split systems can serve 2 to 8 indoor heads on a single outdoor unit, providing whole-home cooling without ductwork.

Does central AC come with heating?

Central AC alone provides cooling only. A central heat pump uses the same configuration but provides both cooling and heating year-round.

Are mini splits ugly?

Wall-mounted heads are visible but increasingly streamlined. For homeowners who object to the appearance, ceiling cassette or concealed ducted indoor units provide more discreet options.

Which is better for a home with allergies?

Central AC with a high-MERV media filter handles whole-home filtration. Mini splits have basic filtration at each head but lack the central-filter approach. For allergy-driven decisions, central AC has a slight edge unless the mini splits are paired with separate IAQ equipment.