Gas furnace replacement cost in Brentwood comes down to one range and a short list of things about your house. Gas furnace replacement costs $4,500 to $7,500. The old furnace comes out, a new one sized to your rooms goes in, and we connect the venting and the gas line and start it with you in the house.
What a gas furnace replacement costs in Brentwood
The $4,500 to $7,500 range is for the whole swap, not just the box. See our heating installation service for the full scope. The low end is a straight change-out where the furnace sits in easy reach. The high end is a job with tight access, new venting or duct work that has to happen first.
If the furnace has already quit, ask for the written furnace quote here and we will set the visit. We walk the house, measure, and put the equipment, the scope and the price on paper before anyone touches the old unit.
You also get a straight comparison. If a repair makes more sense than a new furnace, we say so and show both numbers.
What moves your furnace quote
Every line below can push your number up or down.
| Factor | How it moves the price |
|---|---|
| Size | Set by a room-by-room load calculation, not by copying the old nameplate. |
| Furnace location | An attic hatch, a hallway closet and a garage corner each take different labor. |
| Venting | New or re-run flue pipe adds time and material. |
| Gas line | We check the line and its connection before pricing. |
| Duct condition | We check the duct trunk and returns before the quote, because a new furnace pushed through a bad return gets noisy. |
Brentwood has flat-street ranch houses and canyon lots off Mandeville and Sullivan. Access to the furnace and to the pad or attic is part of what we look at. A hand-carried unit up a hillside takes longer, and we tell you that up front.
Ducts are the line people skip. If they need sealing, resizing or a new trunk, that is written as its own line. Our ductwork services crew can scope it on the same visit.
Gas line, venting and the permit
Natural gas in Brentwood comes from SoCalGas, so the gas connection and the flue are checked as part of the job. If you ever smell gas, leave the house first and call SoCalGas or 911 from outside.
Replacing a furnace is permitted work. Brentwood sits inside the City of Los Angeles, so the permit comes from LADBS. We handle the permit paperwork when your project needs it.
Title 24 Part 6 is California's Building Energy Efficiency Standard. Depending on the scope, a change-out can require duct sealing and a duct leakage test, verified by a third-party HERS rater who is not the installer. We price that into the quote so it is not a surprise on install day.
California law also requires carbon monoxide alarms in homes with a fuel-burning appliance, a fireplace or an attached garage.
Repair first or replace now
Not every failed furnace needs replacing. A hot surface igniter or control board runs $219 to $530 installed, and a blower motor $420 to $1,600 depending on whether the unit uses an ECM. Our heating repair team prices the fix in writing.
A failed heat exchanger or a repair bill that keeps growing points the other way. In that case we lay the replacement quote next to the repair so you decide with both numbers in hand.
What to have ready when you book
You do not need to prepare much. A few details make the visit faster:
- A photo of the label on the furnace
- Where the furnace sits and how we reach it
- Any rooms that never get warm
- Whether you want a heat pump priced next to the furnace
We cover Brentwood and the canyons around it, and you can see more on our Brentwood service area page. We answer the phone around the clock.
Furnace replacement questions
Who pulls the permit for a furnace swap in Brentwood?
The permit comes from LADBS. We handle the paperwork when the project needs it and arrange the inspection after the install.
Will my existing ducts work with a new furnace?
Sometimes. We measure static pressure and test for leakage, then tell you whether the ducts can stay, need sealing, or need the trunk and returns resized as part of the job.
Can I get a heat pump quote instead?
Yes. We lay the furnace and a heat pump side by side for your house, so you see both prices before you choose.
What happens on install day?
The crew protects floors, removes the old furnace, sets the new one, connects the venting and gas, and starts it. We check airflow against the design numbers and set the thermostat with you.
How do I get the quote?
Use the form above or call. A tech visits, measures, and you receive a written estimate before work starts.
Ready to price it? Call (877) 702-9609 and Brentwood Air will book your furnace visit.
Need Professional HVAC Service?
Our HVAC-experienced technicians are ready to help with all your AC and heating needs. Contact Brentwood Air today for expert service throughout the Brentwood and the canyons around it service area.
