Common Myths Your HVAC Professional Wants to Bust

May 16, 2025

If you’ve ever Googled an HVAC question at 11:30 PM because something “didn’t sound right,” you’re not alone. Homeowners across San Antonio (and nearby areas like Helotes, Converse, Universal City, and Alamo Heights) do it every day—especially when the South Texas heat won’t let up.

The internet can be a great resource… but it also spreads a lot of HVAC myths that lead to higher energy bills, avoidable breakdowns, and shortened system lifespan. So let’s clear the air with a few of the most common misconceptions Cowboys Air Conditioning & Heating hears from homeowners in Bexar County and surrounding communities like Boerne and New Braunfels.

Below are the myths your HVAC professional wants to bust—plus what you should do instead for better comfort, efficiency, and peace of mind.


Myth #1: “My Air Conditioner Doesn’t Need Maintenance If Nothing Is Wrong”

This is one of the most expensive myths out there—because your AC can be “working” while silently developing problems.

A properly trained technician doesn’t just check whether cold air is coming out. During a maintenance visit, they inspect critical electrical components, refrigerant performance, airflow, drainage, and overall system health. The goal is to catch issues early—before you’re stuck without cooling during a 100°+ week in San Antonio.

What happens when you skip maintenance?

  • Small issues (weak capacitors, loose wiring, dirty coils, clogged drains) get worse

  • Your system runs longer to cool the same space

  • Energy bills creep up

  • Surprise breakdowns become more likely during peak summer demand

What to do instead:
Schedule annual HVAC maintenance (and twice-yearly service if you have a heat pump). Cowboys AC also offers a yearly maintenance plan that includes an annual AC tune-up, annual furnace inspection, repair discounts, and priority scheduling—helpful when everyone in San Antonio is calling during a heat wave.


Myth #2: “Refrigerant Is Something That Needs to Be ‘Topped Off’”

Refrigerant doesn’t get “used up” like gas in a car. In a correctly operating system, refrigerant circulates through a sealed loop. If you’re low, there’s usually a leak or another underlying issue that needs attention.

Why this myth is dangerous:
If someone keeps “topping off” refrigerant without fixing the real problem, your AC may:

  • Cool poorly or inconsistently

  • Ice up the indoor coil

  • Run hotter/longer than it should

  • Put extra strain on the compressor (an expensive part)

What to do instead:
If your home in San Antonio, Boerne, or New Braunfels isn’t cooling like it used to—or you notice warm air, icing, or longer run times—book a professional diagnostic. A proper repair focuses on the cause (like leaks, airflow problems, or metering device issues), not just a temporary refill.


Myth #3: “Closing Vents in Unused Rooms Saves Money”

It seems logical: close a couple vents, cool less space, spend less money… right?

In reality, closing supply vents can increase static pressure in your duct system. That can make your blower work harder, reduce overall airflow, and sometimes even contribute to comfort issues like hot spots and uneven temperatures.

What can happen when you keep vents closed?

  • Reduced airflow and higher system strain

  • No real energy savings (your system still runs to satisfy the thermostat)

  • Potential duct leakage becomes more noticeable

  • Rooms that are open may feel less comfortable

What to do instead:
If you want real room-by-room comfort, consider solutions that are designed for it—like zoning or ductless mini-splits. Cowboys AC offers ductwork services (including inspections, balancing, sealing, and replacement) and ductless options that can be ideal for additions, garages, or rooms that never seem to match the rest of the house.


Myth #4: “Bigger AC = Better Cooling”

Not always. In fact, an oversized air conditioner can be a comfort and efficiency problem—especially in humid seasons.

Oversized systems often cool too quickly and shut off before completing a full cycle. That can lead to:

  • Short-cycling (rapid on/off)

  • Poor humidity control (the house feels clammy)

  • Uneven temperatures

  • More wear and tear on components

What to do instead:
When it’s time for an AC replacement, get a properly sized system based on your home’s needs. Cowboys AC provides full system installation with energy-efficient options and can help you choose equipment that fits your home, lifestyle, and budget—without the guesswork.


Myth #5: “Cranking the Thermostat Lower Cools the House Faster”

Turning your thermostat down to 60° won’t make the AC blow colder air “faster.” Most systems cool at a steady rate. Setting it extremely low usually just makes the unit run longer—sometimes for hours—driving up energy use and increasing strain.

What to do instead:

  • Use a smart thermostat (and make sure it’s programmed correctly)

  • Change your air filter regularly

  • Keep blinds/curtains closed during the hottest part of the day

  • Make sure airflow isn’t blocked by furniture or rugs over vents

Cowboys AC offers smart thermostat programming and controls to help homeowners get better energy control and long-term savings.


Myth #6: “All HVAC Companies Are Basically the Same”

HVAC work is one of those areas where training, licensing, and process matter a lot. Cowboys Air Conditioning & Heating is a family-owned local company, founded in 1985, and provides 24/7 emergency service—plus installs and services Trane systems as an Authorized Trane Dealer.

That combination of experience, availability, and accountability makes a real difference when your AC stops working on a weekend—or your heater quits during a sudden cold snap.


Need Help With HVAC in San Antonio or Nearby?

If you’re dealing with rising energy bills, uneven cooling, short-cycling, or you just want to stay ahead of breakdowns, Cowboys Air Conditioning & Heating is ready to help across the San Antonio area—including communities like Boerne and New Braunfels.

Call Cowboys Air Conditioning & Heating at (210) 495-7771 to schedule HVAC repair, installation, or maintenance.
You can also visit them at 6510 Blanco Rd, San Antonio, TX 78216.

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