AC Installation in Wilmington, DE
A new air conditioner in Wilmington will run from June through September every year. Tell us about the house, and a licensed contractor who covers New Castle County will get in touch.
Tell us about the job
It takes about a minute.
Four months of real heat, every year
Wilmington summers average 85°F in the afternoon, June through September. That is the stretch a new air conditioner has to handle every year it's in your home.
New Castle County also sees its share of severe weather. Over the past ten years the area logged 228 damaging wind events and 20 hail events, one hailstone as large as 1.5 inches. A new system should go in secured with that in mind. Any unit built since 2023 has to meet a federal minimum of 14.3 SEER2, so that baseline is already covered.
- 4 months
- June through September, your air conditioner is on duty
- 85°F
- the average summer afternoon it cools against
- 20 hail events
- in ten years, and hail bends the fins on outdoor coils
- 13.4 SEER2
- the federal minimum any new unit must meet
NOAA nClimDiv, 1991–2020 normals
Going above the federal minimum saves little here, about $10 a year.
Estimates for a typical New Castle County home, from EIA household energy data, Delaware fuel prices and NOAA climate normals. Your home will differ.
Delaware requires HVAC contractors to hold a state license.
Delaware licenses HVAC contractors through the Board of Plumbing, Heating, Ventilation, Air Conditioning and Refrigeration Examiners. That license is issued to the contractor, not to the job, so it is the business behind your install that has been tested and recorded by the state, not the unit itself.
For the installation, most cities and counties require a permit from the local building office and an inspection once the work is done. That inspection is what checks the actual install in your home, separate from the license the contractor already holds.
Sources: Delaware Code Online · Delaware Division of Professional Regulation
- What size air conditioner does my house need?
- The right size comes from a load calculation, not the square footage of your house alone. A contractor works out how much heat your house gains factoring in your insulation, your windows, how much shade you get, and how many people live there. Going bigger than what the calculation says is not a safety margin, it is a mistake. An oversized unit cools the air fast then shuts off before it pulls the humidity out of the room, so the house feels clammy even at the right temperature.
- Should I replace the whole system or just the outdoor unit?
- In most cases you want to replace both the outdoor unit and the indoor coil together. They are matched to work at a specific efficiency and capacity, and pairing a new outdoor unit with an old indoor coil usually gives up much of the efficiency you are paying for. It can also void the manufacturer warranty on the new equipment. A contractor can look at the age and condition of your indoor coil and tell you whether it can carry on with a new outdoor unit or whether it needs to go too.
- Do HVAC contractors in Wilmington need a state license to work on my home?
- Yes. Delaware requires HVAC contractors to hold a state license, issued by the Board of Plumbing, Heating, Ventilation, Air Conditioning and Refrigeration Examiners. Ask to see the license number before work starts, and you can check it against the board's records.