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By CR Score, the highest-ranked HVAC contractor in Stewartville, MN is Tonna Mechanical: Heating, A/C, Water Treatment, Plumbing & Duct Cleaning with a CR Score of 65/100. It has 4.9★ from 3,341 Google reviews. It is open 24/7. K & S Heating, Air Conditioning, Plumbing & Electrical (#2) and Blue Ox Heating & Air (#3) follow. We ranked 41 HVAC contractors on ten factors, last updated October 22, 2026.
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ContractorsRanked ranks 41 HVAC contractors serving Stewartville, MN. 3 of them are based in Stewartville; the rest serve it from nearby towns. Another 13 within 25 mi are listed but not ranked yet. Counts are as of October 2026.
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13 ranked HVAC contractors in Stewartville post 24/7 hours. The highest-ranked are Tonna Mechanical: Heating, A/C, Water Treatment, Plumbing & Duct Cleaning (#1), K & S Heating, Air Conditioning, Plumbing & Electrical (#2) and Blue Ox Heating & Air (#3). Haley Comfort - Heating, Air Conditioning & Fireplaces - 24/7 Service (#5) also lists emergency service. Hours come from each business's Google listing as of October 2026, so call to confirm.
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17 of 41 ranked HVAC contractors post Saturday hours and 16 post Sunday hours. The highest-ranked open Saturdays are Tonna Mechanical: Heating, A/C, Water Treatment, Plumbing & Duct Cleaning (#1), K & S Heating, Air Conditioning, Plumbing & Electrical (#2) and Blue Ox Heating & Air (#3). Posted hours are office hours; crews may book weekend jobs separately.
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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 Stewartville. Prices were last checked October 2026. Get at least two written quotes before you hire.
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The median Google rating among 41 rated HVAC contractors in Stewartville is 4.8★, with a median of 16 reviews. K & S Heating, Air Conditioning, Plumbing & Electrical has the most, 4,071 reviews, and ranks #2. We adjust ratings for review count, so a few five-star reviews cannot top the list.
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In Minnesota, 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.
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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.