Yes, in almost every case you need a permit to replace an AC in Los Angeles. Swapping out a central air conditioner, heat pump or furnace in the City of LA generally requires a mechanical permit from LADBS, and cities like Burbank, Glendale, Pasadena, Beverly Hills and West Hollywood have their own building departments with similar rules. On top of the permit, California's Title 24 Part 6 energy code applies to HVAC changeouts, and depending on the scope, a third-party HERS rater may need to verify the system before the permit can be finaled.
That sounds like bureaucracy, and some of it is. But the permit and testing exist for practical reasons, and skipping them can create real headaches later. Here's what's involved and what a good contractor should handle for you.
When You Need an HVAC Permit in Los Angeles
Exact requirements vary by city and change over time, so always confirm with your building department. As a general guide, these jobs typically need a permit:
- Replacing a central AC condenser and/or indoor coil
- Replacing a furnace or air handler
- Installing a heat pump, including converting from AC plus gas furnace
- Installing a ductless mini split, single or multi-zone
- Adding, replacing or significantly altering ductwork
- Adding a new system to an addition, garage conversion or ADU
- Electrical work for new equipment, which may need its own electrical permit
Routine repairs, such as replacing a capacitor, contactor, fan motor or thermostat, or fixing a refrigerant leak, generally don't require a permit. Neither does regular maintenance.
Which department handles your permit?
| Where you live | Building department |
|---|---|
| City of LA (Sherman Oaks, Studio City, Encino, Van Nuys, North Hollywood, Hollywood and more) | LADBS (Los Angeles Department of Building and Safety) |
| Burbank | City of Burbank building division |
| Glendale | City of Glendale building division |
| Pasadena | City of Pasadena building division |
| Beverly Hills | City of Beverly Hills building division |
| West Hollywood | City of West Hollywood building division |
| Unincorporated LA County areas | LA County building and safety |
Many LA neighborhoods have city-sounding names but are inside the City of Los Angeles. If you're not sure, check your property tax bill or ask your contractor. You can find general information at ladbs.org.
What Is Title 24 Part 6?
Title 24 is California's building standards code. Part 6 is the energy code, which the California Energy Commission updates on a regular cycle. It applies to new construction and to alterations, which is why an HVAC changeout in an existing home is covered.
For HVAC work, Title 24 Part 6 sets requirements around equipment efficiency, duct insulation and sealing, and verification that the system was installed to work as designed. California sits in the federal Southwest region for efficiency standards, which sets higher minimums for central AC. Since January 2023 equipment has been rated with SEER2 and HSPF2.
The practical takeaway: the energy code doesn't just care what you buy. It cares how it's installed, which is where HERS testing comes in.
HERS Verification: What It Is and What Gets Tested
HERS stands for Home Energy Rating System. For HVAC permits, it means an independent third-party rater, separate from your contractor, comes out to verify that certain parts of the installation meet code. The installer completes compliance documentation, the rater tests and registers the results, and the city inspector looks for that documentation before finaling the permit.
Which tests apply depends on what was installed, what was changed and the current version of the code. The most common ones are:
Refrigerant charge verification
Confirms the system has the right amount of refrigerant. Incorrect charge is one of the most common installation problems in the industry. Too little or too much refrigerant reduces capacity and efficiency and can shorten compressor life.
Airflow (and sometimes fan efficiency)
Checks that enough air is moving across the indoor coil. Low airflow, often from undersized or restrictive ducts, filters or returns, hurts performance and can cause coil freezing. Depending on scope, the blower's power draw may also be checked.
Duct leakage testing
When ducts are added, replaced or altered, or in some cases when the system is replaced, the duct system may need to be pressure-tested for leakage. If it leaks too much, it has to be sealed and retested. In LA, where many homes have old ducts in hot attics, this test often reveals significant leaks the homeowner had no idea about.
Why this matters to you: HERS tests check exactly the things that determine whether your new system actually cools the house on a 105°F Valley afternoon. A system with the wrong charge or leaky ducts can be brand new and still underperform.
Want a pro to take a look?
$55 service call with code LA55 — inspection, diagnosis and a clear price before any work. Open 7 days · 8 AM – 10 PM.
Why Unpermitted AC Swaps Can Hurt You Later
Some installers offer a lower price by skipping the permit. It can look like a saving at the time. Here's why it often isn't. This is general information, not legal advice; talk to the appropriate professional about your specific situation.
Selling your home
California home sales involve seller disclosures and buyer inspections. Inspectors often note HVAC equipment that's newer than the permit history suggests, and buyers or their agents may ask for permits. Unpermitted work can lead to negotiation, requests for retroactive permitting, or delays at an inconvenient moment.
Claims and paperwork friction
If there's ever damage tied to the HVAC system, such as a water leak from a condensate line or an electrical problem, the question of whether the work was permitted and inspected may come up when you deal with your insurance company. A permit and final inspection give you documentation that the work was reviewed. Without it, the conversation can get harder.
Rebates and documentation
Utility rebate programs from LADWP, SCE, Burbank Water and Power, Glendale Water & Power and others change often, and some ask for proof of a permitted installation. Skipping the permit can mean skipping the rebate.
Performance and safety
Permits and HERS testing are a second set of eyes. They catch wrong refrigerant charge, poor airflow, leaky ducts, undersized wiring and unsafe gas or venting connections on furnaces. Those are problems you'd otherwise discover through high bills, poor cooling or worse.
Can you fix it after the fact?
Often, yes. Many building departments allow work to be permitted after installation, though it may require inspection, HERS testing and corrections if something isn't up to code. If you've bought a home with unpermitted HVAC work, a contractor can help you understand what it would take.
Refrigerants, A2L Systems and the Permit Process
Under the EPA AIM Act, new residential AC and heat pump systems manufactured from January 1, 2025 use lower-GWP A2L refrigerants such as R-454B or R-32. These refrigerants have specific installation requirements, which is one more reason a proper permit and inspection make sense on new installs. Existing R-410A systems can still be serviced and repaired. Our article on the R-410A phase-out and A2L refrigerants goes deeper, and if you're on the fence, see repair or replace your AC.
What a Proper Contractor Should Handle
When you get quotes for an AC replacement or heat pump installation, use this checklist to compare them:
- Load calculation to size the system, not a guess based on the old unit
- Exact equipment model numbers in writing
- Mechanical permit (and electrical, if needed) pulled by the contractor
- Title 24 compliance documentation completed
- HERS testing scheduled and coordinated, with any corrections handled
- Duct inspection and sealing if ducts are part of the scope
- City final inspection scheduled
- Utility rebate paperwork, if a program applies
- Startup, testing and verification before the crew leaves
If a quote is noticeably cheaper and doesn't mention any of this, ask why. Often the difference is exactly the steps that protect you.
Common Myths About HVAC Permits in LA
"It's a like-for-like swap, so no permit is needed"
Replacing equipment with a similar unit in the same spot is still generally treated as an alteration that needs a mechanical permit. Title 24 requirements, including HERS verification where applicable, can apply to changeouts too, not just new installs.
"The permit is just a fee"
The fee is the smallest part. The value is in the inspection and testing that confirm the system is charged correctly, moving enough air and safely connected. Those are the things that decide whether a new system actually performs.
"HERS testing means my contractor did something wrong"
No. HERS verification is a standard step on many jobs in California. A well-installed system should pass, and a good contractor welcomes the independent check.
"Mini splits don't need permits"
Ductless systems involve refrigerant piping, electrical circuits and condensate drainage, and they generally need a permit like any other HVAC installation. See our mini-split installation page for how we approach them.
What to Expect on Permit Day
For a typical changeout, the sequence looks like this:
- Before the job: contractor sizes the system, provides a written quote and applies for the permit.
- Install day: old equipment comes out, new equipment goes in, and the system is started up and tested.
- HERS visit: the rater performs the required tests. If anything fails, the contractor corrects it and the rater retests.
- City inspection: the inspector checks the installation and documentation and finals the permit.
Timelines vary by city and season. During heat waves, the AC can usually run while inspections are pending, so you're not left without cooling.
How Back2Cool Handles Permits and Title 24
We size every system with a Manual J style load calculation, pull the permit, handle Title 24 testing and file utility rebate paperwork: the steps cheaper bids quietly skip. Before work starts, you get a written quote with exact model numbers. During the job, floors are covered, the site is cleaned daily and old equipment is hauled away. Before we leave, we verify the system is operating properly.
We work with homeowners, landlords, property managers and commercial clients across Los Angeles, from Sherman Oaks and Studio City to Beverly Hills, West Hollywood and Pasadena.
"Okay so first time an HVAC company ever left me a gift after a job!!! Didn't see that coming at all. And honestly the whole visit was like that. They covered the floors, double checked everything, and explained what they did without me even asking. HVAC companies have always been kind of a headache for me, but these guys were sooooo different 10/10, already told a couple friends about them"
Bohdan B. · Google
Not sure whether your old system needs replacing? Send us a photo of your system and we'll tell you straight whether it needs replacing or just a repair. Call (626) 635-4095 or contact us.