Fremont HVAC that keeps you comfortable, whatever the season brings.
We're a local crew on Bay Street fixing, installing and caring for heating and cooling systems across Fremont. Call us and you'll talk to someone who lives nearby, who gets a technician to your door and gives you the price before any work starts.
ComfortFlow HVAC is a heating and air conditioning company based at 4127 Bay St in Fremont, CA. We repair and install air conditioners, furnaces, heat pumps, ductless mini-splits and water heaters in every Fremont neighborhood, plus Newark, Union City and Milpitas. Prices are flat-rate and approved before work begins, and a real person answers (510) 602-2968 24/7.
How we can help
From a noisy furnace to a whole-home heat pump, one call covers it.
AC repair
Warm air, strange noises or no power at all. We diagnose on the first visit and carry common parts on the truck.
Furnace repair
No heat, short cycling or a pilot that won't stay lit. Safety check included.
Heat pumps
Efficient all-electric heating and cooling. We'll help you find the rebates that apply.
Ductless mini-splits
Comfort for ADUs, additions, garages and rooms the main system doesn't reach.
Water heaters
Tank and tankless repair and replacement, often the same day.
24/7 emergency
Nights, weekends and holidays. Call and a real person answers.
HVAC in Fremont is its own kind of job
Fremont is mild most of the year, which hides how hard local systems work in the weeks that matter. Warm Springs and the Mission San Jose hillsides can run 10 degrees hotter than Ardenwood on the same September afternoon, while foggy winter mornings near the bay keep furnaces cycling from November into February. Sizing equipment for the neighborhood, not just the square footage, is the difference between a system that copes and one that is comfortable.
The rules are changing too. The Bay Area Air District’s zero-NOx standards apply to new water heaters manufactured from 2027 and new furnaces from 2029, and every replacement in Fremont needs a city permit and, in most cases, Title 24 HERS testing. We handle the paperwork and give you an honest comparison between repairing your furnace, replacing it or moving to a heat pump.
Your neighbors on Bay Street
ComfortFlow is based at 4127 Bay St in Fremont. Our technicians know the homes here, from Niles bungalows to newer builds in Warm Springs, and they treat yours with care: shoe covers on, clear explanations, and a clean workspace when they leave.
More about us →Serving every corner of Fremont
And our neighbors in Newark, Union City and Milpitas.
See the service area →Guides for Fremont homeowners
The Bay Area’s gas furnace and water heater rules, explained for Fremont homeowners
Water heaters in 2027, furnaces in 2029. What the Air District rules require, what they do not, and how to plan your next replacement.
Heat pump or gas furnace? An honest comparison for Fremont homes
Upfront cost, monthly bills, comfort and the 2029 rule, side by side for a typical Fremont home.
How much does a new air conditioner cost in Fremont?
Real price ranges by system type, the five things that move the number, and how to compare quotes fairly.
Questions we hear often
What HVAC services do you offer in Fremont?
AC repair and installation, furnace repair and replacement, heat pumps, ductless mini-splits, water heaters, indoor air quality, duct cleaning, smart thermostats, maintenance plans and 24/7 emergency service.
How much does an HVAC service call cost in Fremont?
We charge a flat diagnostic fee that we quote on the phone. Repairs are priced flat-rate and approved by you before we start. Most Fremont repairs fall between $150 and $650.
Do you offer same-day HVAC service in Fremont?
Yes. Most calls placed before early afternoon get a same-day visit, and our 24/7 line handles nights, weekends and holidays.
Are you licensed and insured?
Yes. ComfortFlow is licensed by the California Contractors State License Board and fully insured.
Which areas do you serve?
All of Fremont, including Mission San Jose, Irvington, Niles, Centerville, Warm Springs, Ardenwood and more, plus Newark, Union City and Milpitas.
Should I repair or replace my HVAC system?
If the repair costs more than a third of a new system, or the system is over 15 years old with a major failure, replacement is usually better value. We give you both prices and let you decide.
Too warm, too cold, or just not right?
Give us a call. We'll listen, ask a few questions and find a time that works for you.