Best HVAC Contractors in Commack, NY (2026)
Commack is central Suffolk — Smithtown Township, inland, no coastal exposure. Housing is dominated by 1960s–1980s split-levels and bi-levels on quarter-acre lots, with ductwork that's the single biggest determinant of comfort.
Top HVAC contractors in Commack
Home+ Air and Heat (Homets Services, LLC)
Local Nassau-based dispatch, Manual J / D / S on every install, PSEG-LI Participating Contractor, 10-yr parts + labor 1–10 yrs by Home+ package (Standard / Comfort / Infinite).
See Commack pricing & bookHart Home Comfort
Strong central-Suffolk presence with reliable scheduling into Commack and Smithtown.
T.F. O'Brien Cooling & Heating
Mitsubishi Diamond Elite — the right answer when a Commack split-level needs a ductless zone instead of forcing the trunk line.
Flanders Heating & Air Conditioning
Established Suffolk independent for high-efficiency retrofits.
Housing stock & ductwork
Split-level Commack homes were built with single-zone ducted systems that struggle to balance bedrooms against the lower-level den. Two-stage or variable-speed equipment plus a properly placed thermostat (or a second zone) solves more comfort complaints than a SEER upgrade does. Static-pressure testing on the existing return is a basic test the strongest contractors run.
Permits, utility & local quirks
Commack falls under the Town of Smithtown Building Department for permits. Current incentive eligibility and amounts must be confirmed in writing for the exact customer, equipment, project, contractor, installation date, funding, and rules. National Grid serves most of Commack for gas — oil-to-gas conversions are still active here on older blocks where buried oil tanks are at the end of their service life.
Get a written estimate from Commack's #1-ranked installer
Manual J sizing, model-number-specific proposal, rebate filing handled at install. No high-pressure sales.
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FAQ — Commack HVAC contractors
Why does my Commack split-level have hot bedrooms in summer?
Split-levels create three thermal zones from one thermostat. Upper bedrooms run 4–8°F warmer than the lower den because the supply runs are shorter and unbalanced. The fix is two-stage equipment with an ECM blower and a balanced or zoned duct system — not a bigger AC. Bigger usually makes humidity and short-cycling worse.
Do Commack homes need permits for AC replacement?
Yes. The Town of Smithtown Building Department requires a permit for new condensers, line-set changes, and electrical disconnects. The contractor pulls the permit and the inspection should be included in the price.
Should I replace my Commack oil furnace with gas or a heat pump?
Compare the installed scope, projected operating assumptions, ductwork, electric service, gas availability, and oil-tank work for each option. Federal 25C ended for property placed in service after December 31, 2025. Any current PSEG Long Island, state, manufacturer, or income-qualified program must be confirmed in writing. A good estimate gives you both numbers before unconfirmed incentives.