AC Installation in Janesville, WI
A new air conditioner in Janesville will run from June through August every year. Tell us about the house, and a licensed contractor who covers Rock County will get in touch.
Tell us about the job
It takes about a minute.
Three months of heat, and hail that tests what sits outside
Janesville only asks for cooling three months a year, June through August, with afternoons averaging 81°F. That is a short season, but a new air conditioner still has to be sized right for it, not just hooked up and left to run.
Rock County has logged 41 hail events and 78 damaging wind events over the past ten years, hail up to 2 inches at its worst. That is what an outdoor unit sitting in a yard here has to hold up against. Any new central air conditioner installed now also has to meet the federal minimum of 13.4 SEER2, so the efficiency floor is already set. What is left to get right is the sizing and the install itself.
- 3 months
- June through August, your air conditioner is on duty
- 81°F
- the average summer afternoon it cools against
- 41 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 $20 a year.
Estimates for a typical Rock County home, from EIA household energy data, Wisconsin fuel prices and NOAA climate normals. Your home will differ.
Wisconsin requires contractors to register with the state.
That registration puts the business on file with the Department of Safety and Professional Services, nothing more. Nobody tested this contractor's work, and the state doesn't hold a trade exam an installer has to pass to get on that list. Wisconsin also keeps counties and cities from layering on their own HVAC license, so this record is the same wherever in Rock County you are.
For an air conditioner install, the permit is what actually checks the work. Most cities and counties require one from the local building office before a contractor replaces an AC, and an inspector looks at the finished install once the work is done. That inspection, not the registration, is what catches a unit put in wrong.
Sources: Wisconsin Legislative Reference Bureau · Wisconsin Department of Safety and Professional Services
- What size air conditioner does my house need?
- The right size depends on your home's square footage, insulation, window count and layout, not just a rule of thumb. A contractor works this out with a load calculation, which looks at your specific house rather than a general estimate. Going bigger than you need is not better. An oversized unit cools the air fast but shuts off before it pulls the humidity down, so the house feels clammy even at the right temperature.
- Should I replace the whole system or just the outdoor unit?
- In most cases the outdoor unit and the indoor coil need to be matched, so replacing one without the other can cause problems even if the old part still runs. If your system is older, the manufacturer may no longer make a coil that pairs correctly with a new outdoor unit. A contractor can check what you have and tell you whether the indoor and outdoor sides can be mixed or need to go together.
- Do HVAC contractors in Janesville need a state license to work on my home?
- Wisconsin requires HVAC contractors to register with the state through the Department of Safety and Professional Services. This registration is separate from any local permit requirements that may apply to the installation. Ask to see a contractor's registration before work starts, since it confirms they are recognized to do this work in the state.