Idaho HVAC Pros
Overhead view of an air conditioning condenser unit on a concrete pad next to a house with asphalt shingle roofing and vinyl siding.

AC Installation in Lewiston, ID

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

Tell us about the job

It takes about a minute.

Step 1 of 3: Equipment
Overhead view of a gray outdoor AC condenser unit on a concrete pad beside a mulched garden bed and a house with vinyl siding.

Two months of real heat, then done

Lewiston only asks for cooling in July and August, with afternoons averaging around 82°F. That's a short season, but a new air conditioner still has to be sized and installed to handle those peak afternoons without struggling.

Any new central air conditioner installed now has to meet a federal minimum of 13.4 SEER2. That's the floor, not a feature, so it's worth asking what efficiency the unit you're getting actually carries.

2 months
July through August, your air conditioner is on duty
82°F
the average summer afternoon it cools against
13.4 SEER2
the federal minimum any new unit must meet
Isometric cutaway illustration of a house interior showing ducted air handling equipment and duct runs through rooms, connected by piping to an outdoor condenser unit on a pad outside the wall.
Your air conditioner works hardest from July through August.

NOAA nClimDiv, 1991–2020 normals

An outdoor air conditioning condenser unit mounted on a concrete pad next to a blue-sided residential house at sunset.

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

  • A higher-efficiency unit$100 a year
  • A new unit at the federal minimum, 13.4 SEER2$120 a year

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

Idaho requires HVAC contractors to hold a state license.

Idaho licenses HVAC contractors through the state's HVAC Board. That means the contractor was tested and is on record with the state before taking on work like this. The license covers the contractor, not the job itself.

For this installation, that license is what stands behind the person doing the work. In most cities and counties here, installing an air conditioner also needs a permit from the local building office. An inspection follows once the work is done.

Sources: Idaho Legislature · Idaho Division of Occupational and Professional Licenses

What size air conditioner does my house need?
It depends on your square footage, your ceiling height, how much shade your house gets, and how well it holds cold air. A contractor works this out with a load calculation, not a chart that just looks at square feet. Putting in one that is too big cools the house fast but shuts off before it pulls the humidity down, so the air feels damp. One that is too small runs constantly and still struggles to keep up on the hottest afternoons.
Should I replace the whole system or just the outdoor unit?
If your indoor coil and outdoor unit are different ages or different efficiency levels, replacing just the outdoor unit can cause problems. The two are matched at the factory to work together, and pairing an old coil with a new condenser often means the system never reaches the efficiency it is rated for. A contractor can check the age and condition of the coil, the ductwork, and the refrigerant lines before telling you whether the system needs to go or just the outdoor unit.
Do HVAC contractors in Lewiston need a state license to work on my home?
Yes. Idaho requires HVAC contractors to hold a state license, issued by the state's Heating, Ventilation and Air Conditioning Board. Installing a new air conditioner also usually needs a permit from the local building office, with an inspection once the work is done. Ask to see the license before any work starts on your home.
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