AC Installation in Decatur, IL
A new air conditioner in Decatur will run from June through September every year. Tell us about the house, and a licensed contractor who covers Macon County will get in touch.
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Four months of real heat, and storms in between
Decatur asks for cooling from June through September, and summer afternoons average 84°F. That is not extreme heat, but it is steady, and a new system has to keep up with it day after day for a full season.
Macon County also sees its share of rough weather. Ten years of records show 47 hail events and 109 damaging wind events, with hail up to 2.5 inches. The outdoor unit sits exposed to all of it, so the coil and cabinet matter as much as the size of the system. Any new central air conditioner installed now also has to meet the federal efficiency minimum of 13.4 SEER2.
- 4 months
- June through September, your air conditioner is on duty
- 84°F
- the average summer afternoon it cools against
- 47 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
A higher-efficiency unit would save about $40 a year to run in Macon County compared with a new unit at the federal minimum.
Estimates for a typical Macon County home, from EIA household energy data, Illinois fuel prices and NOAA climate normals. Your home will differ.
In Illinois, HVAC licensing for homes is left to the cities and towns.
Macon County does not run its own contractor license, and Illinois has no state license behind it either. What rule exists, if any, comes from the city or town the house is in rather than from any state record.
Most cities and counties require a permit before an air conditioner gets installed, along with an inspection once the work is done. That inspection is what checks the refrigerant lines, the electrical connection and the condensate drain were put in correctly. In a place with no state or county license, that permit and inspection are the record this job leaves behind.
Source: Illinois General Assembly
- What size air conditioner does my house need?
- The right size depends on your house, not a rule of thumb like square footage alone. A contractor works this out with a load calculation that accounts for your insulation, windows, ceiling height, and how much shade your house gets. An oversized unit cools the air fast but shuts off before it pulls the moisture out, so the house feels clammy. Undersized, and it runs nonstop on those 84°F afternoons and still falls behind. Either way, get the calculation done rather than matching the size of the old unit.
- Should I replace the whole system or just the outdoor unit?
- In most cases replacing just the outdoor unit is not a good idea, and a contractor will likely steer you away from it. The outdoor and indoor units are matched to work together, and pairing a new condenser with an old evaporator coil often means losing efficiency and sometimes the manufacturer warranty on the new part. If your indoor coil is old enough that the outdoor unit needs replacing, it is usually close behind. A contractor can check the age and condition of both and tell you whether the coil is worth keeping.
- Do HVAC contractors in Decatur need a state license to work on my home?
- Illinois does not license HVAC contractors at the state level for residential work. That is left to cities and towns, so check whether Decatur requires a local license or permit before you hire someone.