Top 7 Most Common HVAC Problems and How to Fix Them

Your HVAC system works hard to keep your home or business comfortable—but when it stops working, frustration sets in fast. At Tarrant Mechanical, we get dozens of calls from DFW homeowners and property managers dealing with the same handful of issues.

Here are the 7 most common HVAC problems, how to fix them (when possible), and when to call the pros.

1. Dirty or Clogged Air Filters

Problem:

Restricted airflow, reduced efficiency, and dusty indoor air.

Fix:

Replace filters every 1–3 months. If you have pets, allergies, or smoke indoors, replace them more frequently. This is the easiest and most overlooked HVAC maintenance task.

Tip:

Mark your calendar or sign up for a Tarrant Mechanical maintenance plan—we’ll handle it for you.

2. Thermostat Issues

Problem:

The system won’t turn on, runs continuously, or doesn’t reach the set temperature.

Fix:

• Replace batteries
• Ensure it's set to "cool" or "heat" as needed
• For smart thermostats, update the firmware or reset the device

When to Call Us:

If recalibrating doesn’t work, it could be a wiring or sensor issue that needs professional attention.

3. Refrigerant Leaks

Problem:

System blows warm air, cycles frequently, or forms ice on the coils.

Fix:

This is not a DIY job. HVAC refrigerants are regulated and require licensed technicians to inspect and recharge the system properly.

Why It Matters:

Low refrigerant can cause long-term compressor damage. Tarrant Mechanical handles leak detection, repair, and full recharge services.

4. Dirty Condenser or Evaporator Coils

Problem:

Reduced cooling efficiency and higher energy bills.

Fix:

• Turn off the system
• Gently rinse the outdoor unit with a hose
• Schedule a coil cleaning service annually for deeper buildup

Preventive Measure:

Keep the area around your outdoor unit clear of grass, leaves, and debris.

5. Frozen Evaporator Coil

Problem:

The system may freeze due to airflow problems, dirty filters, or low refrigerant levels.

Fix:

• Turn off the system to allow it to thaw
• Replace the air filter
• Call Tarrant Mechanical to inspect refrigerant levels and airflow

Tip:

Frozen coils can lead to water damage if left unchecked—don’t delay repairs.

6. Unusual Noises

Problem:

Banging, squealing, rattling, or hissing sounds can point to loose parts, worn belts, or duct issues.

Fix:

Some sounds indicate minor fixes, while others require urgent attention.

• Squealing = belt issue
• Rattling = loose parts
• Hissing = duct leaks or refrigerant leaks

When to Call:

If the sound is persistent or loud, it’s best to let a professional investigate.

7. Short Cycling

Problem:

System turns on and off rapidly without completing a full cycle—leading to inefficient cooling and stress on the unit.

Fix:

This may stem from:

• A clogged air filter
• Thermostat problems
• Oversized or failing system

Call the Experts:

Short cycling often indicates a bigger underlying issue. Let us diagnose and fix it before your compressor burns out.

When Should You Call Tarrant Mechanical?

If you’ve done basic troubleshooting and the problem persists, it’s time for professional help. We offer:

• 24/7 emergency HVAC service across DFW
• Transparent pricing and fast response
• Residential, commercial, and industrial expertise
• Over a decade of trusted HVAC repairs

Prevent Problems Before They Start

Most of these HVAC issues can be avoided with regular maintenance. Tarrant Mechanical offers seasonal tune-ups and maintenance plans to help:

• Catch issues early
• Improve energy efficiency
• Extend system lifespan
• Ensure clean, safe indoor air

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