It is 95 degrees outside, the AC is running, and your house will not cool down. If you are standing in front of a vent waiting for cold air that never quite arrives, take a breath. You are not alone. After years of diagnosing this exact problem in homes across Los Angeles and Ventura Counties, we can tell you that in most cases, the fix is simpler and more affordable than you might think.
The most common reasons an air conditioner stops cooling are a tripped breaker, a clogged air filter, a dirty outdoor unit, frozen evaporator coils, a refrigerant leak, or a thermostat set incorrectly. Most of these are basic repairs, and you can check two of them yourself right now.
Before you pick up the phone, there are a few things you can safely try:
Confirm the thermostat is set to Cool mode and the fan is set to Auto, not On. It sounds basic, but a bumped thermostat dial, or a mode accidentally switched to Heat, is one of the most frequent reasons for a service call. This problem requires no repair at all. If you have a smart thermostat, verify the schedule has not reverted to a default program.
Find your AC’s breaker in the main electrical panel, switch it fully off, wait ten seconds, and switch it back on. Power surges and grid fluctuations are common in Los Angeles during summer heat waves and can trip a breaker without you realizing it.
If the breaker trips again immediately after resetting, stop there and call a licensed technician. A breaker that keeps tripping indicates an electrical fault that requires professional diagnosis.
A dirty, clogged filter restricts airflow across the evaporator coil. That restricted airflow forces the system to work harder and can cause the coil to freeze over, which shuts down cooling entirely. Swap in a fresh filter.
This single step resolves more “AC not cooling” calls than any other. In Los Angeles, filters clog faster than the national average because of smog, pollen, dust, and wildfire ash. Replace them every one to three months, and every month during peak summer use.
Walk outside and check the condenser unit. Clear away any leaves, debris, or overgrown plants so there is at least two feet of clearance on all sides. A blocked condenser cannot release heat efficiently, which reduces cooling inside the home.
Checked all four, and the house still is not cooling? Stop troubleshooting and call a licensed contractor. Everything beyond these steps, such as refrigerant, electrical components, the compressor, or the evaporator coil, involves real safety risks and specialized tools. Trying to fix these yourself can turn a small problem into a costly one.
A professional AC repair service can accurately diagnose the problem and restore your system safely and efficiently.
Choosing a reputable HVAC contractor is one of the most important decisions. Learn what to look for in our guide on How to Choose a Trustworthy HVAC Contractor.
Book a Diagnostic Visit → (818) 722-1332. The $95 diagnostic fee is credited toward any repair we perform.
If the safe checks above did not solve the problem, one of these issues is likely at work:
If you see ice on the indoor unit or refrigerant lines, or feel almost no airflow from the vents, the evaporator coil has likely frozen over. Do not try to diagnose or service it while frozen. Instead, turn the thermostat to Fan Only and let the blower run until the ice fully melts.
A frozen coil is almost always caused by an airflow restriction (clogged filter, closed vents) or low refrigerant underneath. Finding that root cause is where a trained technician comes in.
Refrigerant does not get “used up.” If levels are low, there is a leak somewhere in the system. Low refrigerant reduces the system’s ability to absorb heat from indoor air, resulting in warm air from the vents, longer run times, and eventually compressor damage. By law, refrigerant handling requires EPA Section 608 certification.
This is not a DIY repair. A licensed technician will locate the leak, repair it, and recharge the system to the manufacturer’s specification.
The outdoor condenser coil releases the heat your system pulls from inside the house. When that coil is coated with dirt, dust, or wildfire ash, heat transfer drops, and cooling performance suffers. In the San Fernando Valley and inland LA communities, condenser coils get dirty faster due to higher dust levels and longer cooling seasons.
Annual professional coil cleaning, which is included in every Care Club maintenance visit, prevents this from becoming a cooling failure.
These electrical parts start and run the compressor and fan motors. When they weaken or fail, the system may short-cycle (turn on and off rapidly), blow warm air, or fail to start at all. Capacitors are the most common part to fail during Los Angeles heat waves because high temperatures speed up electrical wear.
A technician can test these components in minutes.
The compressor circulates refrigerant between the indoor and outdoor coils. When it fails, the system blows room-temperature or warm air because the refrigerant is no longer removing heat from the home. Compressor failures are usually caused by electrical problems, refrigerant leaks, restricted airflow, or normal wear after 10 to 15 years of heavy use.
In LA’s long cooling season, compressors run more hours each year than in most other regions, which speeds up wear.
Your AC extracts moisture from indoor air as it cools. That moisture drains through a condensate line. When the line clogs, which frequently occurs in humid coastal areas and after dusty Santa Ana wind events, water backs up into the drain pan.
Many systems have a safety float switch that shuts down cooling when the pan fills, protecting against water damage but leaving you without cold air. A technician clears the line and checks that the switch is working.
According to ENERGY STAR, 20 to 30 percent of conditioned air can be lost through duct leaks, holes, and poor connections. Many older Los Angeles homes were built with duct insulation levels below current California Title 24 requirements.
The result: you paid for cooling that leaks away inside your attic or walls before it ever reaches the living space. Duct sealing and insulation upgrades are often the most cost-effective improvement a homeowner can make. Learn about our duct services.
This is a common myth: “A bigger AC will cool better.” That is not true. Your ductwork is designed to move a specific volume of air. Pushing more air through the same ductwork creates higher static pressure and more friction, and can actually deliver less cold air to the rooms, not more.
Proper cooling depends on matching equipment capacity, duct sizing, and airflow. A real CFM (cubic feet per minute) calculation should be done before any equipment change, especially now that California’s Ultra-Low NOx furnace standards have changed how air moves through residential systems.
LA homes have their own personality, and so do their cooling problems:
Grid instability damages equipment. When the power grid strains during heat waves, voltage fluctuations and rolling blackouts take a toll on HVAC electronics. We have seen a clear increase in capacitor and control board failures tied to these events. Installing a surge protector on the outdoor unit is inexpensive insurance against an expensive electrical repair.
Older duct insulation quietly steals your cool air. Many older LA homes have attic ductwork insulated below current standards. Depending on your climate zone and duct location, upgrading insulation and sealing leaks can recover a significant portion of the cooling capacity you are already paying for but never receiving.
Inaccessible ductwork makes system design more complicated. Many LA homes have ducts buried inside walls where they cannot be reached. When ductwork cannot be accessed, designing a properly balanced comfort system is genuinely difficult. This is one reason why a thorough, experienced contractor is so important here.
Wildfire smoke speeds up filter and coil contamination. After any significant smoke event, filters might require replacement within days instead of months, and condenser coils should be inspected and cleaned. Learn more about protecting your air quality during wildfire season.
When cooling problems get serious, the real question is whether your system is worth fixing. We do not guess, and we do not upsell. We use an objective scoring system that considers what really matters:
the age of the equipment, how many hours it runs each year, how long you plan to stay in the home, the cost of today’s repair, potential energy savings from a modern system, the refrigerant type (older R-22 systems are extremely expensive to recharge due to the EPA phase-out, while R-410A remains serviceable and newer systems use lower-GWP R-454B), and the likelihood of future repairs.
Low scores mean repairing is your best value. High scores mean replacement is the smarter long-term decision. The numbers, not a sales pitch, show you the best option. We walk you through them during a free replacement consultation.
We have a detailed guide on whether to repair or replace your HVAC system to help you make an informed decision.
LADWP currently offers rebates of up to $2,500 per ton on qualifying heat pump replacements, which can make upgrading much more affordable.
We believe in honest pricing:
The diagnostic and service call fee is $95, and that amount is credited toward the cost of any repair we perform. You are never paying twice. Simple labor-only repairs start at a $350 minimum. Refrigerant leak repairs vary by system type and leak location.
Airflow and duct repairs range from reconnecting a disconnected duct run to a full duct redesign with an installation crew. We will tell you which after we look.
We would rather give you an honest range than a tempting number we cannot stand behind.
Our technicians are factory-trained, EPA Section 608 certified, and NATE-recognized. We hold a C-20 contractor’s license (CSLB #1081403) and run fully stocked service vans, so most repairs are handled in a single trip.
As a locally owned, women-led company with branches in Chatsworth and Simi Valley, we serve all of Los Angeles and Ventura Counties. We back every job with a workmanship guarantee.
Here is what that looks like in practice, in a customer’s own words:
“My furnace kept acting up and, after three visits from another technician didn’t solve it, I contacted Affordable based on a video I found during a Google search. Allen came out and recommended a cost-effective solution as opposed to pricier alternatives I was initially open to exploring.
During his inspection he discovered an unrelated problem with the A/C coil that surely would have led to water damage come summer. The following day technicians came out and installed new equipment and so far, so good. My initial impression is that they are a reliable company that will stand by their work.“ — Laura D.
Two things matter in that story. The technician recommended the cost-effective option over the pricier one because that was the honest call. His trained eye also caught a coil issue that would have caused water damage that very summer.
Most “AC not cooling” emergencies are avoidable with consistent preventive care:
Join a Care Club maintenance membership for bi-annual professional service covering your entire system.
Schedule professional maintenance every six months: spring before the cooling season and fall before the heating season. This way, small issues get caught before they become hot-day breakdowns. Change your filter every one to three months between visits to keep airflow strong.
Our full-system maintenance includes a 27-point tune-up with static pressure testing, refrigerant-level checks, condenser and evaporator coil cleaning, blower motor inspection, electrical connection checks, condensate drain clearing, thermostat calibration, ductwork leak inspection, and seismic strap checks for earthquake safety.
The most common causes are a clogged air filter restricting airflow, a tripped circuit breaker, low refrigerant from a leak, dirty condenser coils, a frozen evaporator coil, or a failing electrical part such as a capacitor or compressor.
LA-specific factors like extended heat waves, grid instability, wildfire smoke, and older ductwork can make these failures happen more often.
Switch the thermostat to Fan Only and let the blower run until the ice fully melts. Do not try to diagnose or repair the system while the coil is frozen. Once thawed, a licensed technician can identify the root cause, which is usually an airflow restriction or low refrigerant charge.
Yes. A clogged filter restricts airflow across the evaporator coil, which can cause the coil to freeze over and stop cooling. In Los Angeles, filters clog faster than average because of smog, dust, pollen, and wildfire ash. Replacing the filter is the most common and easiest fix.
Power surges and grid changes during LA heat waves can trip circuit breakers, damage capacitors, or affect control boards. Reset the breaker once. If it trips again or the system does not restart normally, a technician should check the electrical parts.
We recommend surge protectors on outdoor units to prevent this kind of damage.
The diagnostic fee is $95 and is credited toward any completed repair. Simple labor-only repairs start at $350. Refrigerant leak repairs and ductwork vary by system and scope. Affordable Heating and Air provides transparent, upfront pricing before any work begins.
Consider replacement if the system is over 15 years old, the repair costs more than half the price of a new system, the unit uses R-22 refrigerant (which is very expensive to recharge), or your energy bills have gone up a lot.
LADWP rebates of up to $2,500 per ton on qualifying heat pump replacements can make upgrading more affordable than you might expect.
Yes. Our Simi Valley branch at (805) 755-4074 provides the same diagnostic, repair, and maintenance services across all of Ventura County, including Simi Valley, Moorpark, Thousand Oaks, Oxnard, Ventura, and Camarillo.
You have checked the thermostat, reset the breaker, changed the filter, and cleared the outdoor unit. The house is still warm. That is exactly when it is time to bring in a licensed pro who will diagnose the real problem and fix it right the first time.
Los Angeles County: (818) 722-1332 Ventura County: (805) 755-4074
Book a Diagnostic Visit → $95 diagnostic credited toward repair. Join Care Club → bi-annual maintenance so you never face this again.
Serving Chatsworth, Northridge, Granada Hills, Porter Ranch, West Hills, Van Nuys, Encino, Woodland Hills, Glendale, Burbank, Santa Clarita, and all of Los Angeles County. Also serving Simi Valley, Moorpark, Thousand Oaks, Oxnard, Ventura, Camarillo, and all of Ventura County.