Heating & Air Conditioning in Fairfield, CA
Aarvaks installs and repairs heat pumps, ductless mini-splits, furnaces and air conditioning in Fairfield and across Solano County. Posted prices are the same here as everywhere we work, and every installation starts with a written quote.
What Fairfield’s Codes Mean for an HVAC Replacement
Three sets of rules apply when a heating or cooling system is replaced in Fairfield: the permit, California’s energy code for Climate Zone 12, and the Bay Area Air District’s furnace standard.
Permits for HVAC Work
California’s Mechanical Code, which Fairfield enforces, makes it unlawful to install, alter, repair, or replace a regulated mechanical system without a permit. Exemptions include portable heating and cooling units. Aarvaks handles permit coordination for Fairfield and every city and county we serve as part of the project scope.
Energy Code for Climate Zone 12
Fairfield is in California Building Climate Zone 12. Under the 2025 Energy Code, in effect since January 1, 2026, installing new heating or cooling components on a ducted system requires a duct leakage test: 10% leakage or less, 7% or less to the outside, or every accessible leak sealed. New duct sections need R-8 insulation. In Climate Zone 12, refrigerant charge must also be verified when refrigerant components are installed or altered, with airflow of at least 300 cubic feet per minute per ton.
Bay Area Air District — Zero-NOx Furnaces from 2029
The Air District’s Rule 9-4 sets a zero-NOx standard for furnaces with a 2029 compliance date. The District says the requirement applies only when current equipment burns out, so it does not require replacing a working furnace. A heat pump burns no fuel, so it meets the standard.
Heating and Cooling Fairfield Homes
Fairfield has about 40,400 housing units. 47% were built from 1960 through 1989 and 42% since 1990, and 61% heat with utility gas, according to the Census Bureau’s 2020–2024 American Community Survey.
Replacing Gas Heat
61% of Fairfield homes heat with utility gas and 34% with electricity. When a gas furnace needs replacing, a ducted heat pump on the same ducts provides both heating and cooling, and it can also replace an aging central air conditioner. Furnace installation starts at $7,500, AC installation at $10,000, and a single-zone heat pump at $17,000.
Homes From the 1970s Through the 2000s
37% of Fairfield’s housing was built in the 1970s and 1980s and 31% in the 1990s and 2000s. Under the state energy code, ducts are tested for leakage when new heating or cooling equipment goes in. Duct condition is assessed and documented during the estimate visit before any equipment recommendation is made.
Detached Homes
69% of Fairfield’s housing units are detached single-family homes. Ductless mini-splits heat and cool homes without ductwork and rooms the ducts do not reach. A single-zone mini-split starts at $6,500.
Fairfield’s Climate and Your Heating and Cooling Load
At NOAA’s Fairfield weather station, average daily highs reach 89–90°F in July and August, and average lows fall to 40°F in December and January (1991–2020 normals). The station averages 2,307 heating degree days and 1,113 cooling degree days a year.
Hot Summer Afternoons
The station averages 60 days a year at 90°F or above and 11 at 100°F or above. Cooling degree days run about 270 a month in July and August, so cooling capacity has to cover the hottest afternoons.
Cold Winter Nights
Heating degree days run about 510 a month in December and January, and the station averages 8 nights a year at 32°F or below.
One System for Both
With heating degree days about twice the cooling degree days, Fairfield has a large load in both seasons, and a heat pump does the work of a furnace and an air conditioner with one outdoor unit.
HVAC Services in Fairfield
Installation, repair, and maintenance for all residential and commercial HVAC systems throughout Fairfield. All brands serviced. $79 residential diagnostic fee. Permit coordination included on all installations.
Heat Pump Installation & Repair
Ducted heat pump installation for Fairfield homes with existing ductwork — replaces gas furnace and central AC in one system upgrade. Single-zone systems starting at $17,000. Carrier Authorized Dealer. 10-year limited parts warranty. All brands serviced for repair.
Mini-Split Installation & Repair
Ductless mini-splits for homes without ductwork. No duct modification required. Single-zone systems starting at $6,500. Carrier, Mitsubishi, and Bosch systems. Multi-zone configurations for whole-home comfort without ductwork.
Heating & Air Conditioning
Furnace installation, repair, and tune-up. Central AC installation and repair. All brands serviced. $79 residential diagnostic fee. Furnace installation starting at $7,500. AC installation starting at $10,000. 10-year limited parts warranty.
Heat Pump Incentives for Fairfield Homeowners
The federal heat pump tax credit has expired, and the TECH Clean California and HEEHRA single-family programs are reserved statewide. Program availability changes. We identify what applies to your project during the estimate.
MCE Heat Pump Rebate
Fairfield is in MCE’s service area, with PG&E delivering the power. MCE lists a rebate of up to $400 per 500 square feet for installing a heat pump heating and cooling system, for customers who own and have lived in their single-family detached home for at least 12 months. The system must be installed by an MCE participating contractor, who processes the application.
Carrier Cool Cash
Carrier Cool Cash offers up to $2,100 on qualifying Carrier heating or cooling products purchased August 1, 2026 through November 20, 2026. Equipment must be installed and the claim submitted by December 20, 2026.
Federal & State Programs
The federal Section 25C credit for qualifying heat pumps covered equipment placed in service through December 31, 2025. TECH Clean California’s single-family heat pump HVAC incentives were reserved statewide as of November 14, 2025, and HEEHRA single-family rebates were fully reserved statewide as of February 24, 2026.
All incentive claims should be verified at the time of your installation. Aarvaks does not guarantee rebate availability or tax credit eligibility for any specific installation. Current programs for every county are on our rebates page.
Frequently Asked Questions
Do I need a permit to replace my furnace or air conditioner in Fairfield?
Yes. California’s Mechanical Code, which Fairfield enforces, requires a permit to install, alter, repair, or replace a regulated mechanical system, with exemptions such as portable heating and cooling units. Aarvaks handles permit coordination for Fairfield as part of the installation scope.
What does the Bay Area furnace rule mean for my Fairfield home?
The Bay Area Air District’s Rule 9-4 sets a zero-NOx standard for furnaces with a 2029 compliance date. The District says it applies only when current equipment burns out, so a working furnace does not have to be replaced. A heat pump burns no fuel and meets the standard.
What does California’s energy code require when I replace HVAC equipment in Fairfield?
Fairfield is in Building Climate Zone 12. Under the 2025 Energy Code, installing new heating or cooling components on a ducted system requires a duct leakage test, with a limit of 10% total leakage or 7% to the outside, or every accessible leak sealed. New duct sections need R-8 insulation. In Climate Zone 12, refrigerant charge must also be verified when refrigerant components are installed or altered, with airflow of at least 300 cubic feet per minute per ton. Ducts registered as previously sealed, or built with asbestos materials, are exempt from the leakage test.
How much does heat pump installation cost in Fairfield?
Ducted heat pump installation, replacing a gas furnace and central AC with one heat pump on the existing ducts, starts at $17,000 for a single-zone system. Ductless mini-split installation starts at $6,500 for a single zone. Final cost depends on zone count, equipment selection, duct condition, and electrical scope, and we provide a written itemized quote before any work begins. Book online or call 510-848-5010.
Are there heat pump rebates for Fairfield homeowners in 2026?
MCE, which serves Fairfield, lists a heat pump heating and cooling rebate of up to $400 per 500 square feet for customers who own and have lived in their single-family detached home for at least 12 months, installed by an MCE participating contractor. Carrier Cool Cash offers up to $2,100 on qualifying Carrier products purchased through November 20, 2026. The federal Section 25C tax credit covered equipment placed in service through December 31, 2025, so it does not apply to 2026 installations. TECH Clean California’s single-family heat pump HVAC incentives were reserved statewide as of November 14, 2025, and HEEHRA single-family rebates were fully reserved statewide as of February 24, 2026. We identify what applies during the estimate.
Are your prices the same in Fairfield?
Yes. Our posted starting prices are the same in Fairfield as in every city we serve, and each job gets a written, itemized quote before work begins.
Schedule HVAC Service in Fairfield
Get an in-home assessment and a written, itemized quote.