Your Goodman AC is running but your Las Vegas home is not getting cool. This is one of the most common service calls we receive during summer, and the causes range from a 5-minute DIY fix to a repair that requires professional equipment. This troubleshooting guide walks you through the most common reasons a Goodman system stops cooling effectively in Las Vegas heat, what you can check yourself, and when you need to call a licensed technician.
Before You Call: 5 Things to Check Yourself
1. Check Your Air Filter
A clogged air filter is the number one cause of reduced cooling in Las Vegas — and the easiest to fix. Las Vegas's desert dust, combined with pet dander and household debris, can clog a standard filter in 3-4 weeks during peak summer. A severely restricted filter starves the evaporator coil of airflow, causing ice formation on the coil that blocks cooling entirely.
What to do: Turn off the system. Locate your air filter (typically in the return air grille or at the air handler). If the filter is visibly dirty or clogged, replace it immediately. Turn the system back on after 30 minutes (to allow any ice to melt) and check if cooling improves. During Las Vegas summer, change your filter every 30 days without exception.
2. Check Your Thermostat Settings
Verify the thermostat is set to COOL mode (not HEAT or FAN ONLY), the fan is set to AUTO (not ON), and the setpoint is at least 3-5 degrees below the current room temperature. Also check that the thermostat has power — dead batteries in a wireless thermostat or a tripped breaker can cause the system to stop calling for cooling.
3. Check the Circuit Breakers
Your Goodman system has two breakers: one for the indoor air handler/furnace and one for the outdoor condensing unit. If the outdoor breaker is tripped, the indoor fan will blow air but it will not be cool (the compressor needs power to cool refrigerant). Reset the breaker. If it trips again immediately, do not keep resetting it — this indicates an electrical fault that requires professional diagnosis.
4. Check the Outdoor Unit
Go outside and verify the outdoor condensing unit is running. The fan should be spinning and you should feel warm air blowing upward from the unit. If the fan is not spinning, check the disconnect switch (the small box near the unit) — someone may have pulled the disconnect during maintenance and not replaced it. Also check for debris: landscaping waste, tumbleweeds, or pool equipment blocking airflow around the unit can cause the system to overheat and shut down on safety limits.
5. Check for Ice on the Indoor Coil or Lines
Look at the refrigerant lines (the copper pipes connecting the indoor and outdoor units). If either line has frost or ice on it, your system has a problem — either low refrigerant charge, restricted airflow, or a faulty metering device. Turn the system off completely and let the ice melt (1-3 hours) before calling for service. Running the system with ice on the coil can damage the compressor.
Common Causes That Require Professional Repair
Low Refrigerant (Leak)
If your Goodman system is low on refrigerant, it cannot absorb enough heat from your indoor air to cool effectively. Refrigerant does not wear out or get used up — if it is low, there is a leak somewhere in the system. Symptoms include reduced cooling, ice on the lines, and the system running constantly without reaching setpoint.
Repair cost: $200-$600 for leak detection and refrigerant recharge, plus $300-$2,500 if the leak requires coil repair or replacement.
Failed Capacitor
The capacitor provides the electrical boost that starts the compressor motor. When it fails, the outdoor unit fan may run but the compressor will not start — resulting in the fan blowing air but no cooling happening. Capacitor failures are extremely common in Las Vegas due to extreme heat stress.
Repair cost: $150-$400 including diagnosis, part, and labor.
Dirty Condenser Coil
The outdoor condenser coil must reject heat from the refrigerant to the outdoor air. When the coil is coated with Las Vegas dust, dirt, cottonwood seeds, or mineral deposits from hard water irrigation overspray, it cannot reject heat efficiently. The result is reduced cooling capacity, higher electricity bills, and eventually compressor overheating and shutdown.
Repair cost: $150-$300 for professional coil cleaning. This is part of an annual AC tune-up and should be performed every spring before the cooling season begins.
Failed Contactor
The contactor is an electromagnetic switch that sends power to the compressor and fan motor when the thermostat calls for cooling. Over time, the contact points arc and pit, eventually failing to close and deliver power. A failed contactor means no power reaches the compressor even though the thermostat is calling for cooling.
Repair cost: $175-$400 including diagnosis, part, and labor.
Frozen Evaporator Coil
Multiple issues can cause the evaporator coil to freeze: low refrigerant, restricted airflow (dirty filter or collapsed duct), failed blower motor, or a stuck metering device. A frozen coil blocks all airflow and stops cooling completely. The system must be turned off to allow the ice to melt before the root cause can be diagnosed.
Repair cost: Varies based on root cause — $100 for a filter change to $2,500+ for a coil replacement.
Failed Compressor
The worst-case scenario. If the compressor has failed mechanically or electrically, no cooling is possible. Goodman's lifetime limited compressor warranty (when registered) covers the compressor part for the original owner; you pay labor ($800-$1,500) and related materials. On an unregistered or out-of-warranty system, total compressor replacement cost is $2,000-$4,500.
Goodman-Specific Diagnostic Codes
Many Goodman systems display diagnostic LED codes on the circuit board inside the outdoor unit. If you can safely open the access panel, look for a blinking LED light. Common Goodman codes include:
- 1 flash: System operating normally
- 2 flashes: High-pressure lockout (overheating — check condenser coil cleanliness and airflow)
- 3 flashes: Low-pressure lockout (low refrigerant or restricted metering device)
- 4 flashes: Open circuit (electrical connection problem)
- Continuous on: Control board failure
Write down the code before calling for service — it helps your technician prepare with the correct parts and tools.
Frequently Asked Questions
Why is my Goodman AC running but not cooling in Las Vegas?
The most common causes are a clogged air filter (restricting airflow and causing the coil to freeze), low refrigerant from a leak, or a failed capacitor that prevents the compressor from starting while the fan continues to run. Start by checking and replacing your air filter — this solves the problem roughly 30% of the time with no service call needed. If a filter change does not restore cooling, you likely need professional diagnosis.
How much does it cost to fix a Goodman AC that is not cooling?
Repair costs range widely depending on the cause: $0 for a filter change or thermostat adjustment, $150-$400 for a capacitor or contactor replacement, $200-$600 for a refrigerant recharge, or $2,000-$4,500 for a compressor replacement. The average Goodman AC repair in Las Vegas costs $250-$600. A professional diagnostic ($75-$125) identifies the specific cause and gives you an exact repair quote before any work begins.
Is my Goodman AC too small for Las Vegas heat?
Possibly. If your system cools adequately during spring and fall but cannot maintain setpoint when outdoor temperatures exceed 110 degrees, the system may be undersized. This is common when a system was sized for a different climate or when home modifications (room additions, window changes, removed shade trees) have increased the cooling load. A professional Manual J load calculation determines whether your system is correctly sized. However, before concluding the system is too small, verify that the condenser coil is clean, refrigerant charge is correct, and ductwork is not leaking — these issues mimic the symptoms of an undersized system.
Should I repair or replace my Goodman AC?
General guideline: if the repair costs less than one-third of a new system and the existing system is less than 10 years old, repair is usually the right choice. If the repair costs more than half the price of a new system, or the existing system is 12+ years old, replacement is usually the better investment — especially in Las Vegas where a new high-efficiency system will save $200-$500 per year in electricity. Use our Repair or Replace calculator for personalized guidance.