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AC Not Cooling the House
in McKinney, TX
In McKinney, summer temperatures regularly climb past 100°F, and an AC that won't keep up stops being a nuisance and starts being a health risk. The most common reasons are low refrigerant, a clogged coil, or a system that was undersized when it was installed. If you leave it alone, the compressor works harder than it should and burns out sooner.
Quick Answer
When your AC runs but can't cool the house, it's usually low refrigerant, a dirty coil, or an undersized unit struggling against McKinney's summer heat above 100°F. A tech needs to check refrigerant levels and inspect the coil. Don't keep running it and hoping it catches up. Call (361) 317-6400 to get it looked at before it quits completely.
Telltale Signs
Warning Signs to Watch For
- The thermostat is set to 72°F but the house sits at 80°F or higher
- The AC runs almost constantly without ever shutting off
- The air coming from the vents feels only slightly cool, not cold
- Rooms at the far end of the house are noticeably hotter than rooms near the unit
- The outdoor unit is running but the indoor air handler sounds like it's straining
Root Causes
What Causes AC Not Cooling the House?
Low Refrigerant Charge
Refrigerant is the chemical that moves heat out of your home. When a system leaks refrigerant, it can't absorb enough heat from the air inside, so the house stays warm even though the unit is running. McKinney systems work hard from May through September, and small leaks that went unnoticed all winter show up fast once the heat hits.
The Fix
Refrigerant Leak Repair and Recharge
A tech finds the leak, repairs it, and refills the refrigerant to the correct level. Just adding refrigerant without fixing the leak is a short-term patch that won't hold.
Dirty Evaporator Coil
The evaporator coil sits inside your air handler and absorbs heat from your indoor air. When it gets coated in dust and grime, it can't absorb heat properly. McKinney homes that skip annual maintenance build up enough coating on the coil within two or three seasons to cut cooling capacity noticeably.
The Fix
Evaporator Coil Cleaning
A tech pulls the coil or accesses it through the air handler and cleans it with a coil cleaner. A clean coil moves heat the way it was designed to, and the system doesn't have to run nearly as long to reach temperature.
Undersized AC System
A unit that's too small for the square footage it's supposed to cool will run all day and never catch up. In newer developments on the north side of McKinney, homes have been bought and added onto over the years, and the original AC was never upsized to match the added space.
The Fix
Load Calculation and System Replacement
A proper load calculation figures out exactly what size unit the home needs. Replacing an undersized unit with the correct size is the only real fix.
Self-Diagnosis
Which Cause Applies to You?
Check the signs you're observing to narrow down the likely root cause before your inspection.
| What You're Seeing | Low Refrigerant Charge | Dirty Evaporator Coil | Undersized AC System |
|---|---|---|---|
| House is warm even though AC runs all day | |||
| Ice forming on the indoor coil or refrigerant lines | |||
| Hissing or bubbling sound near the indoor unit | |||
| Added a room or addition and cooling got worse | |||
| Airflow from vents feels weak and barely cool |
Free Inspection
Get a Diagnosis in McKinney
An on-site inspection is the only way to confirm which cause applies to your property. Free, no obligation.
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