How long does furnace installation take?

Most like for like furnace replacements finish in a single day, with heat back on that evening. Adding a furnace where ductwork or gas lines need changes runs longer, and the written proposal states the exact timeline before any work starts.

Should I repair or replace my furnace?

If the unit is 15 or more years old and the repair is a major component, replacement usually wins on reliability and gas use. Our furnace repair team lays out both paths with the numbers attached. Nobody here earns commission for talking you into a new unit.

Is a heat pump a better choice than a new gas furnace?

For a lot of Bay Area homes, yes. A heat pump replaces the furnace and the AC with one electric system and qualifies for rebates gas equipment does not. See heat pump installation for the full comparison. When it is close, we quote both and let the numbers argue.

What AFUE rating should I choose?

AFUE is the share of gas that becomes heat in your house. Standard furnaces run around 80 percent; condensing models reach 95 percent and higher but need different venting and a condensate drain. We recommend the tier your home, venting path, and usage justify.

Do you handle permits and city inspection?

Yes. The mechanical permit and the inspection visit are included and coordinated by us in every Bay Area city we serve. You do not deal with the municipality.

What does a new furnace cost?

Every quote is a written line item proposal covering equipment, labor, permit, and disposal, priced after the site visit and load calculation. You approve the exact scope before work starts, and the invoice matches the proposal. Every install carries a three-year labor warranty on top of the manufacturer's warranty on the new equipment.

Furnace Installation in the Bay Area

Furnace Installation.

Your furnace made it through last winter on willpower, and you would rather replace it on your schedule than in a January emergency. That is the right instinct, and it is when most people call us. Onzone installs and replaces furnaces across the Bay Area: gas and electric, single stage to modulating, homes and light commercial.

Every job starts with a Manual J load calculation, because a furnace matched to the house beats a furnace matched to a guess. Most straight swaps take one day, with heat back on that evening. NATE certified installers, permits pulled in every city we work, a written line item proposal the same day we visit. The old unit leaves on our truck.

Problems we fix every day.

Furnace past repair

The heat exchanger, control board, or blower has failed on an aging unit and another repair no longer makes sense.

Rising winter gas bills

An old single stage furnace short cycles and burns more gas than a modern high efficiency unit doing the same job.

Uneven heat room to room

Undersized equipment or tired ductwork leaves bedrooms cold while the hallway thermostat reads satisfied.

Red tagged or unsafe unit

A cracked heat exchanger or a failed safety control means the furnace should not run another season.

Sage Vikky May 2026

I had an amazing experience with Oleg and Teymur! They repaired my AC and furnace, and also installed a new water heater for me. From the beginning they were friendly, professional, and really knew what they were doing. They took the time to explain everything, answered all my questions, and made me feel comfortable throughout the process. It's hard to find people who truly care about doing quality work, but these guys definitely do. Everything is working perfectly now, and I'm very happy with the results. I highly recommend Oleg and Teymur to anyone looking for honest and reliable service!

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Daniil Chapovskyi June 2026

I recently had a new AC and heat pump system installed by Onzone, and I couldn't be happier with the entire experience. From the initial consultation to the final inspection, the team was professional, knowledgeable, and consistently on time. They clearly explained every step of the process, answered all of my questions, and made what could have been a complicated project feel straightforward and stress-free. One thing that really stood out was how respectful they were of my home. The crew kept the work area exceptionally clean throughout the installation and left everything spotless when the job was complete. Their attention to detail was impressive. Onzone also guided me through the permit process from start to finish and made sure everything was done correctly. They coordinated all the necessary inspections and ensured the system successfully passed the HERS test, giving me confidence that the installation met all required standards. Most importantly, the quality of the installation exceeded my expectations. The finished system looks great, operates flawlessly, and performs even better than I imagined. It's clear that they take pride in their work and focus on doing the job right. I highly recommend Onzone to anyone considering an AC or heat pump installation. Professional, reliable, detail-oriented, and truly committed to customer satisfaction.

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Mateo Johnson June 2026

We recently had OnZone Heating & Air install a Cooper&Hunter heat pump for us, and the entire experience was excellent from start to finish. The installation team was prompt, friendly, and professional. They took the time to explain everything they planned to do and made sure we were comfortable with their approach before getting started. Throughout the installation, they were communicative, respectful of our home, and clearly took pride in their work. The system has been performing great so far. It's much quieter than I expected, and the cooling function has been extremely efficient. We'll have to wait until winter to fully test the heating side, but based on our experience so far, I have high expectations.

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Furnace Installation.