+
By CR Score, the highest-ranked HVAC contractor in Flossmoor, IL is Four Seasons Heating, Air Conditioning, Plumbing, & Electric with a CR Score of 63/100. It has 4.8★ from 3,722 Google reviews. It is open 24/7. King Heating, Cooling & Plumbing (#2) and Four Seasons Heating, Air Conditioning, Plumbing, & Electric (#3) follow. We ranked 819 HVAC contractors on ten factors, last updated October 22, 2026.
+
ContractorsRanked ranks 819 HVAC contractors serving Flossmoor, IL. 1 of them is based in Flossmoor; the rest serve it from nearby towns. Another 20 within 25 mi are listed but not ranked yet. Counts are as of October 2026.
+
339 ranked HVAC contractors in Flossmoor post 24/7 hours. The highest-ranked are Four Seasons Heating, Air Conditioning, Plumbing, & Electric (#1), King Heating, Cooling & Plumbing (#2) and Four Seasons Heating, Air Conditioning, Plumbing, & Electric (#3). Hours come from each business's Google listing as of October 2026, so call to confirm.
+
638 of 819 ranked HVAC contractors post Saturday hours and 498 post Sunday hours. The highest-ranked open Saturdays are Four Seasons Heating, Air Conditioning, Plumbing, & Electric (#1), King Heating, Cooling & Plumbing (#2) and Four Seasons Heating, Air Conditioning, Plumbing, & Electric (#3). Posted hours are office hours; crews may book weekend jobs separately.
+
AC replacement typically costs $3,887 to $8,073, with $5,978 typical (Per system, installed (unit plus labor); typical range of customer-reported jobs. US national range). This is a national range, not adjusted for Flossmoor. Prices were last checked October 2026. Get at least two written quotes before you hire.
+
The median Google rating among 819 rated HVAC contractors in Flossmoor is 4.9★, with a median of 20 reviews. Four Seasons Heating, Air Conditioning, Plumbing, & Electric has the most, 27,709 reviews, and ranks #3. We adjust ratings for review count, so a few five-star reviews cannot top the list.
+
In Illinois, furnace and heat pump calls peak in the coldest winter weeks and AC calls in summer heat waves. Spring and fall are the easiest times to book maintenance or a replacement.
+
Each HVAC contractor gets a 0–100 CR Score from ten published factors, led by reputation (25%), credentials (15%), review volume (10%) and trade focus (10%). A business with no Google reviews scores zero on rating, review volume and recency; other factors we cannot measure are left out. Only businesses with a confirmed trade and 3 or more reviews, or a claimed profile, are ranked.