Ofallon, MO
HVAC Pros in Ofallon, MO
14 licensed HVAC pros serve Ofallon, MO. Free-quote requests route to whichever provider can match your ZIP and timing. Spire Missouri rebates up to $400 available.
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Quick facts
- AreaOfallon
- StateMO
- Providers14
- Climate zone4A-Mixed-Humid
- Heating degree days4,700
- Recommended systemdual fuel
Why HVAC matters in Ofallon
Ofallon sits in IECC climate zone 4A-Mixed-Humid with average January temperatures of 33°F and July highs around 76°F. With 1,200 cooling degree days, air conditioning is critical during summer months.
MO (Saint Charles County) falls in IECC 4A-Mixed-Humid. HDD 4700 / CDD 1200 per NOAA 1991–2020 state averages drive a dual fuel HVAC strategy. Climate data is zone-level; consult a contractor for site-specific load calcs.
Dual-fuel system recommended for Ofallon
A dual-fuel system pairs a heat pump with a gas furnace backup — the heat pump runs efficiently on mild days while the furnace handles deep cold.
With 4,700 heating degree days and winter lows reaching 33°F, standard heat pumps lose efficiency. The dual-fuel approach gives you heat pump savings on 80% of winter days plus reliable gas heat when temperatures drop below 15-20°F.
About Ofallon HVAC
Ofallon's suburban profile means most HVAC work is replacement rather than new-build. 14 HVAC providers list active service in Ofallon — a small but workable shortlist. Getting three quotes is realistic if you plan a week out.
Ofallon's winter design temps (January averages near 33°F) sit at the edge of standard heat-pump efficiency, which is why dual-fuel setups — heat pump plus gas furnace backup — have become the contractor-preferred configuration here. Spire Missouri's Spire MO High-Efficiency Gas Furnace Rebate currently offers up to $400 toward a qualifying system, which meaningfully shifts the cost-of-ownership math.
Top local providers
Request quotes →- installationrepairinspectionemergency
What customers say “The quote experience: The comfort specialist (sales and research) who came through and inspected a 900 sq ft condo.…”
- installationrepairinspection
What customers say “Another really good experience with a technician at Jerry Kelly. Jessica was fantastic with her electrical help with…”
- Budget Heating, Cooling & PlumbingTop ratedinstallationrepairemergency
What customers say “The techs that come out initially were very professional and personable. On the day of my system install the employers…”
- B & B Heating & CoolingTop rated
What customers say “10 out of 5 Stars! Justin Popp from B&B Heating & Cooling was absolutely fantastic. He came out this morning and had…”
- Hoff Heating & ACTop rated
What customers say “Honestly, we were about to go with another company, mainly because of the longer parts and labor warranty. But…”
- Stay Cool Climate ControlTop rated
What customers say “Called 3 companies early in the morning. Stay Cool was able for me to take pics of the area while other companies…”
- No Problem Heating and CoolingTop rated
What customers say “NPM was assigned to us by our home warranty company. I submitted a request and the office staff called first thing the…”
- Faszold Heating and CoolingTop ratedinstallationrepairemergency
What customers say “I recently had a new HVAC system installed and had a fantastic experience from the initial consultation through the…”
- Swiss Air Heating & CoolingTop rated
What customers say “We called to have Swiss Air come out to give us pricing to replace our entire HVAC system! Allen was amazing he stayed…”
- Design Aire Heating and CoolingTop rated
What customers say “Josh came and serviced our furnace and humidifiers. He did a very thorough job making sure everything was working…”
- Hosack Plumbing, Heating & CoolingTop ratedinstallationrepairemergency
What customers say “Really appreciate the prompt service and repair that I received from Hosack. Assessed our issue and had a brand new…”
- KirbnJays Heating & CoolingTop rated
What customers say “After a very stressful no-heat situation in the middle of winter, this company absolutely restored my faith in good…”
- Missouri Furnace & Air ConditioningTop rated
What customers say “From the initial phone call with the secretary.. To the actual visit and work on my furnace by James.. the service I…”
What customers say “I recently had One Hour Heating and Air Conditioning of O'Fallon install a new HVAC system at my home, and I couldn’t…”
What Ofallon homeowners say
“Honestly, we were about to go with another company, mainly because of the longer parts and labor warranty. But something just didn’t feel right, especially with their absolutely outlandish loan package. We went back to Markus, who had provided us a …”
“Called 3 companies early in the morning. Stay Cool was able for me to take pics of the area while other companies wanted to come out 3+ days later to look while we had no hot water. Stay Cool was able to come out the same day which was a huge plus fo…”
“I recently had a new HVAC system installed and had a fantastic experience from the initial consultation through the final installation. Dan was the sales representative who visited my home, and he was outstanding. He was extremely thorough during th…”
Local pricing snapshot
Repairs typically run $150–$600. Full system replacements range from $4k for a basic furnace to $12k+ for a premium heat pump. Dual-fuel systems (heat pump + gas backup) are recommended for this area's cold winters.
Available rebates in Ofallon
- Spire Missouri: Spire MO High-Efficiency Gas Furnace Rebate — $150–$400 for furnace
Federal tax credits (up to $2,000 for heat pumps) can stack with utility rebates. See full cost breakdown →
Nearby service areas
Missouri hub →Popular comparisons in Ofallon
- Academy Air Heating, Cooling, Plumbing and Electric vs Jerry Kelly Heating, Air Conditioning, Electrical & Plumbing4.8★ vs 4.9★
- Academy Air Heating, Cooling, Plumbing and Electric vs Budget Heating, Cooling & Plumbing4.8★ vs 4.8★
- Jerry Kelly Heating, Air Conditioning, Electrical & Plumbing vs Budget Heating, Cooling & Plumbing4.9★ vs 4.8★
- Jerry Kelly Heating, Air Conditioning, Electrical & Plumbing vs B & B Heating & Cooling4.9★ vs 5.0★
- Budget Heating, Cooling & Plumbing vs B & B Heating & Cooling4.8★ vs 5.0★
- Budget Heating, Cooling & Plumbing vs Hoff Heating & AC4.8★ vs 4.9★
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Frequently Asked Questions
What's the best heating system for Ofallon?
Ofallon has cold winters (avg January: 33°F) with 4,700 heating degree days. A dual-fuel system (heat pump + gas furnace backup) is recommended — the heat pump handles mild days efficiently while the furnace takes over during deep cold snaps below 15-20°F.
How important is air conditioning in Ofallon?
Very. With 1200 cooling degree days and summer highs regularly exceeding 76°F, AC is essential in Ofallon. Central AC or a heat pump (which provides both heating and cooling) is strongly recommended. Budget $3,500-$7,000 for a quality cooling system installation.
How much does HVAC work cost in Ofallon?
In Ofallon, typical costs range from $150-$600 for repairs, $4,000-$8,000 for a standard furnace or AC replacement, and $6,000-$14,000 for a heat pump system. After available rebates, heat pump installations often net out to $4,000-$9,000. Get 2-3 written quotes to compare — prices vary significantly between contractors.
How do I verify a HVAC contractor is licensed in Missouri?
Missouri does not issue a statewide HVAC contractor license. Each municipality licenses the mechanical trade — Kansas City (MO) requires a Mechanical Contractor license through the City Planning & Development Department, St. Louis City and St. Louis County each have their own mechanical licensing, and Springfield, Columbia, and Independence each maintain local registrations. Always verify the active city license, current general-liability insurance, and any municipal bond. File complaints with the Missouri Attorney General Consumer Protection Division.
Licensing verified weekly. Reviews refreshed within the last 30 days.
Licensing data: Municipal licensing — no statewide Missouri HVAC license (each city regulates mechanical trades independently) · Company data: verified business records + Google Business profile
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