Massachusetts HVAC Pros
An outdoor air conditioning condenser unit positioned beside a blue-sided house at sunset.

AC Installation in Nantucket, MA

A new air conditioner in Nantucket will run from July through August every year. Tell us about the house, and a licensed contractor who covers Nantucket County will get in touch.

Tell us about the job

It takes about a minute.

Step 1 of 3: Equipment
An outdoor air conditioning condenser unit positioned on a concrete pad next to a blue-sided house, surrounded by green shrubs and flowering hydrangeas at sunset.

Nantucket doesn't ask much of an air conditioner, but it still needs to be sized right

Summer afternoons here average 74°F, and most homes only need cooling in July and August. That's a short season, but the unit still has to be matched to the house. One that's too big will cool the air fast and shut off before it pulls the moisture out, leaving the house feeling damp.

Wind is the bigger concern out here. The county has logged 60 damaging wind events over the past ten years, so the outdoor unit needs a solid pad and mounting that can take a coastal gust. Any new system installed today has to meet the federal minimum of 13.4 SEER2, and a licensed contractor can help you decide whether to meet that number or go above it.

2 months
July through August, your air conditioner is on duty
74°F
the average summer afternoon it cools against
1 hail events
in ten years, and hail bends the fins on outdoor coils
13.4 SEER2
the federal minimum any new unit must meet
Isometric cutaway illustration of a small house showing interior rooms with furniture, an indoor air handler with ducts in the attic space, and refrigerant lines running to an outdoor condenser unit on a pad.
Your air conditioner works hardest from July through August.

NOAA nClimDiv, 1991–2020 normals

Aerial view of a square outdoor air conditioning condenser unit on a concrete pad beside a house wall with a sliding glass door.

Going above the federal minimum saves little here, about $20 a year.

  • A higher-efficiency unit$200 a year
  • A new unit at the federal minimum, 13.4 SEER2$220 a year

Estimates for a typical Nantucket County home, from EIA household energy data, Massachusetts fuel prices and NOAA climate normals. Your home will differ.

What size air conditioner does my house need?
That depends on the square footage, how much shade and window area the house has, and how well it holds cool air, so a contractor needs to look at the house to answer it. A unit that is too big cools the air fast but shuts off before it pulls the moisture out, so the house feels clammy. One that is too small runs long stretches and still struggles to keep up. A proper load calculation accounts for all of this in a way that square footage alone cannot.
Should I replace the whole system or just the outdoor unit?
If the indoor coil and outdoor unit are different ages or different efficiency levels, replacing just the outdoor unit can leave you with a mismatch that hurts performance and shortens the life of both. New central air conditioners have to meet a federal minimum of 13.4 SEER2, and an older indoor coil was not built to work with that. A contractor can check whether your existing coil and ductwork can pair with a new outdoor unit, or whether the whole system needs to come out together.
Do HVAC contractors in Nantucket need a state license to work on my home?
Ask to see a license before any work starts. A licensed contractor should be able to show you a number on request, and you can check it against the state's licensing board if you want to confirm it yourself.
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