Furnace Installation & Replacement · Fremont, CA
Furnace Replacement in Fremont, CA
Replacing a furnace in Fremont means removing the old unit, connecting a new one to your ducts and thermostat, and passing a city inspection. We did just that in a Fremont attic with a new high-efficiency Goodman furnace. Upgrade Home Services installs standard 80% and high-efficiency 95% gas furnaces, or a heat pump, and files the Fremont express permit for you. Estimates are free.
- 5.0 on Google · 170 reviews
- Licensed, CSLB #1066776 · B, C-20
- Family-owned since 2002
- Mon–Sat 8 AM–5 PM, closed Sunday

What happened on our Fremont furnace replacement?
The homeowner had an outdated, inefficient furnace in the attic. Rooms were not staying at an even temperature, and energy costs kept rising. We swapped it for a new high-efficiency Goodman furnace and kept the parts of the system that still worked well. The full write-up is on the Fremont furnace replacement project page.
- Out: the aging furnace, safely disconnected and removed.
- Prepared: the system connections, ready for the new unit.
- In: the new furnace, tied into the existing ductwork and thermostat controls.
- Checked: airflow, safe operation and heating performance before we left.
Keeping good ducts and a working thermostat can simplify a job. We only suggest changing them when your home needs it.
How do I know my furnace is ready to be replaced?
Look at the pattern, not one bad night. Uneven temperatures from room to room and bills that keep climbing were the signs in this Fremont home. Frequent breakdowns on an older unit are another. If you’re not sure, start with a heating repair visit: the diagnostic is $89 and is waived when you approve the repair. We’ll tell you plainly whether a fix or a new furnace makes more sense.
He was quickly able to figure out the problem and identify the fix.
Raghavan R., Google review
Should I pick an 80% or a 95% furnace?
Both can be the right call, and we install both. The number is how much of the gas becomes heat for your home. A 95% model is a condensing furnace: it pulls extra heat from its exhaust, which makes water that needs a drain. Which one fits depends on where the furnace sits, how it can vent and how you use your heat. Our heating overview compares the two in more detail, and the estimate is free with a clear written quote.
Could a heat pump replace my furnace instead?
Yes, if you’d like heating and cooling from one electric system. Fremont’s electricity comes from Ava Community Energy, and PG&E delivers the power and supplies gas. As of November 2026, Ava’s Savings & Incentives page has a finder: enter your address to see current offers. You may qualify; call us and we’ll check what applies to your home. Our rebates by city page and heat pump installation page explain more.
| Option | Runs on | Good to know |
|---|---|---|
| Standard 80% gas furnace | Gas | Heating only; pairs with a separate AC |
| High-efficiency 95% gas furnace | Gas | Condensing, so it needs a drain line |
| Heat pump | Electricity | Heats and cools; check Ava’s finder for offers |
Do I need to replace my gas furnace because of new rules?
No. As of November 2026, the Air District’s zero-NOx rules apply to new gas furnaces made from January 1, 2029, and only when a furnace is replaced. A working furnace does not have to be replaced. The Bay Area Air Quality Management District posts the details on its rule implementation page.
What permit does Fremont require for a new furnace?
A Residential HVAC express permit. Fremont’s permit types page lists it for a new furnace or a swap in the original location. You apply online through the Citizen Access portal, and the city issues express permits automatically. Every Fremont permit still gets a building inspection. We file it, meet the inspector and arrange any HERS testing (a third-party energy code check) the job needs.
What other work have we done in Fremont?
Furnaces are only part of it. We repaired and serviced a ductless system that had performance issues on a Fremont mini-split maintenance call. We also cleared built-up lint from a clogged line on a Fremont dryer vent cleaning job.
Who replaces furnaces in Fremont?
Upgrade Home Services is a family-owned team based at 743 Ames Ave in Milpitas, a few minutes south of Fremont. We have worked on Fremont heating systems since 2002 and hold California license CSLB #1066776. Goodman went into the attic job above, and we also install Amana, Carrier, Payne, Daikin and Mitsubishi. Our Alameda County work also reaches Newark, Union City and Sunol, and the full city list takes in much of Santa Clara and San Mateo counties. See our main furnace installation page for more.
Key takeaway: A Fremont furnace swap can often reuse your ducts and thermostat. Choose 80%, 95% or a heat pump, and let us file the express permit and meet the inspector.
Fremont furnace questions
Can a new furnace go in the same attic spot?
Often, yes. Our Fremont job set the new Goodman furnace in the attic, on the existing ducts and thermostat.
Is a 95% furnace always better than an 80% one?
Not always. It depends on your venting, drain options and home. We’ll walk you through both at the free estimate.
Does Fremont inspect furnace replacements?
Yes. Every Fremont permit requires a building inspection, and we schedule it for you.
Can I get a rebate for a new gas furnace?
The local offers we track are mainly for heat pumps. Check Ava’s finder, or call us and we’ll look at your options.
How much is a furnace tune-up?
Furnace maintenance is $135. Comfort Club members get yearly visits and 15% off repairs.
Specials
Simple, upfront prices.
-
$135
AC or furnace tune-up
Cleaning, safety checks and a full system test before the season.
Book now -
$89
Diagnostic visit
Waived when you approve the repair. $49 for Comfort Club members.
Book now -
$399
Air duct cleaning
Up to 10 vents (returns count), $15 per extra vent. Comfort Club members 15% off.
Book now -
$130
Dryer vent cleaning
One-story vent up to 15 ft. $175 for two-story or townhouse. Comfort Club members 15% off.
Book now -
$135
Water heater maintenance
Tank flush. $150 for a tankless descale. Comfort Club members 15% off.
Book now -
Free
New system estimate
A clear written quote for a new or replacement system.
Book now
We aren't comfortable
until you are.
Service, repair or replacement. Tell us what's going on and we'll take it from there. Free estimates on new and replacement systems.
Mon–Sat 8 AM–5 PM · Closed Sunday