It's 103°F in Folsom and your AC is running — but the house just won't cool down. This is one of the most stressful HVAC situations a homeowner can face, especially in July and August when temperatures don't let up even at night.
Before you panic, work through this troubleshooting guide. Some causes are simple DIY fixes. Others require a technician. Knowing which is which can save you time, money, and a very uncomfortable afternoon.
Start Here: Quick Checks Before Calling a Technician
Check Your Thermostat Settings
Make sure it's set to COOL (not HEAT or FAN ONLY), the temperature is set below your current indoor reading, and it's not in a locked or "away" mode. If it's a smart thermostat, check the app — sometimes a scheduling conflict overrides the manual setting.
Check and Replace the Air Filter
A clogged filter is the #1 DIY cause of AC problems. Pull out your filter (usually in the return air vent or at the air handler). If it's gray or visibly clogged, replace it immediately. A heavily clogged filter starves the system of airflow, which can cause coil freezing and dramatically reduce cooling performance.
Check the Outdoor Unit
Go outside and look at your condenser unit. Is the fan spinning? Is there ice forming on the refrigerant lines? Are the coils covered in dirt or cottonwood fluff? If the fan is NOT spinning, you likely have a failed capacitor. If there's ice, turn the system off and run just the fan to thaw it — then call a technician to find out why it froze.
Common Causes That Require a Technician
Failed Capacitor
The capacitor starts and runs the compressor and fan motors. When it fails, the outdoor unit may hum but not run, or the fan may spin while the compressor doesn't. Repair cost: $150–$300. This is one of the most common summer repairs in Folsom — capacitors degrade faster in extreme heat.
Low Refrigerant (Leak)
Refrigerant doesn't get "used up" — if your system is low, there's a leak somewhere. Signs include: ice on refrigerant lines, hissing or bubbling sounds near the outdoor unit, or a system that runs constantly without reaching your set temperature. A technician will find and repair the leak, then recharge the system. Cost: $200–$600 depending on leak location and severity.
Dirty Evaporator Coil
The evaporator coil inside your air handler can accumulate dust and buildup over years of use, especially if filters have been neglected. A dirty coil can't absorb heat efficiently. Cleaning requires accessing the air handler and using coil cleaner — best left to a technician. This is often caught and fixed during a spring tune-up before it becomes a summer problem.
Frozen Evaporator Coil
If ice is forming on the indoor unit or refrigerant lines, the coil has frozen. Causes: low refrigerant, dirty filter, or dirty coil. Turn the system completely OFF (not just fan mode) and let it thaw for 2–4 hours. Then call a technician to determine the root cause — otherwise it will refreeze.
When "AC Not Cooling" Means "Replace the System"
In most cases, an AC that runs but doesn't cool can be repaired. But consider replacement if:
- The compressor has failed and the system is over 12 years old
- The system uses R-22 refrigerant (phased out — recharging costs are very high)
- You've had multiple repairs in the same season
- The repair cost exceeds 50% of a new system's price
We'll always give you an honest assessment — if a repair makes more sense than replacement, we'll tell you that.
AC Not Cooling in Folsom? We Can Be There Today.
We serve Empire Ranch, Broadstone, El Dorado Hills, and all of Folsom with same-day AC repair. Don't wait out a heat wave.
Call (916) 616-3115 NowFrequently Asked Questions
Why is my AC running but not cooling my Folsom home?
The most common causes in Folsom are: a clogged air filter, low refrigerant from a leak, a failed capacitor, a frozen evaporator coil, or a dirty condenser coil. Start by checking your filter and thermostat settings. If those are fine, call a technician for a diagnostic.
Can I fix a frozen AC coil myself?
You can thaw a frozen coil by turning the AC off and running just the fan for 2–4 hours. But a frozen coil almost always has an underlying cause — low refrigerant, restricted airflow, or a dirty coil. Without fixing the root cause, it will freeze again. Call a technician to diagnose why it froze.
How much does AC repair cost in Folsom, CA?
Most AC repairs in Folsom range from $150–$800. A capacitor replacement is typically $150–$300. A refrigerant recharge runs $200–$500 depending on the amount needed and leak repair. We charge a $49 diagnostic fee that is waived if you proceed with the repair.
How fast can Comfortable HVAC Services respond in Folsom?
We offer same-day AC repair service in Folsom, CA including Empire Ranch, Broadstone, and surrounding neighborhoods. Call (916) 616-3115 — we prioritize broken AC calls during summer heat events.
