At Mi Amigo Heating & Cooling, we often receive calls from homeowners who say their air conditioner just isn’t keeping up. A common issue behind poor cooling is improper AC size. If your HVAC unit is too small for your home’s square footage and insulation levels, it will struggle to meet your cooling needs, especially during our brutal Arizona summers. Understanding your system’s HVAC tonnage is key to ensuring comfort and energy efficiency.

1. Your AC Runs All Day, But It’s Still Warm

One of the most obvious signs of an undersized HVAC unit is when it constantly runs. In Peoria’s peak summer heat, an air conditioner will work hard, but it shouldn’t run nonstop.

An undersized HVAC unit lacks the HVAC tonnage (cooling power) needed to meet your home’s demands. As a result, it keeps cycling without ever reaching your desired temperature.

This isn’t just inefficient, it’s also expensive.

2. Some Rooms Are Always Hot

Another clue your AC size might be off? Hot spots throughout your home.

If you’ve noticed that your upstairs bedroom or the back office never cools down properly, your HVAC unit may be too small to distribute air evenly.

Proper HVAC tonnage accounts for your home’s layout, insulation, and sun exposure. A system that’s too small can’t maintain consistent comfort in every room, especially in larger or two-story homes.

3. Your Energy Bills Keep Rising

High utility bills can also indicate an HVAC unit that’s too small.

When your AC size doesn’t match your home’s needs, the system overworks to compensate. That constant strain drives up your electricity costs month after month.

Many Peoria residents assume they need a newer or more efficient system. In reality, they might just need the right-sized one.

4. Your AC Breaks Down Frequently

Over time, an undersized HVAC unit wears itself out.

Because it has to work longer and harder, components like compressors and motors are more likely to fail prematurely. Frequent repairs and short system lifespans are the cost of running the wrong AC size.

At Mi Amigo Heating & Cooling, we often see this with new home builds or recent additions where the original system was never recalculated.

5. The System Struggles on 100°+ Days

During those triple-digit Peoria afternoons, does your home feel more like a sauna than a haven?

That’s a major red flag that your HVAC tonnage is lacking.

Every air conditioner is rated to remove a specific amount of heat per hour. If your AC size is too small, it simply can’t keep up with Arizona’s extreme temperatures, even if it’s running perfectly.

6. Short Cooling Cycles That Don’t Help

Sometimes an undersized HVAC unit will appear to start and stop frequently. These short cycles aren’t because the system is inefficient; they’re usually because it can’t move enough cool air quickly.

This leads to uneven temperatures, humidity issues, and more wear and tear on your unit.

7. High Indoor Humidity

Arizona might be dry most of the year, but during monsoon season, humidity spikes. A properly sized HVAC unit should reduce indoor humidity effectively.

If your home feels sticky or musty inside, even with the AC running, it could be another sign that the AC size isn’t sufficient for your square footage.

What AC Size Should You Have?

Proper HVAC tonnage is based on several factors:

• Square footage of your home
• Ceiling height
• Window quantity and direction
• Insulation levels
• Climate conditions (like Peoria’s desert heat)

A general rule is that you need 1 ton of cooling per 500–600 square feet. But every home is different, which is why professional load calculations are essential.

Don’t Guess your AC size, Get a Professional Assessment

At Mi Amigo Heating & Cooling, we don’t believe in guesswork. Our team performs detailed Manual J load calculations to determine the correct AC size for your home. Whether you’re replacing an old unit or upgrading your cooling system, getting the HVAC tonnage right from the start saves you thousands in the long run.

The Right AC Size Means Better Comfort and Lower Bills

Choosing the right AC size isn’t just about cooling; it’s about protecting your investment. An undersized HVAC unit causes:

• Poor comfort levels
• Higher energy costs
• Shorter system lifespan
• More frequent breakdowns

Don’t let a small system leave your home sweating this summer.

Schedule Your AC Evaluation Today

If you suspect your AC size might be too small, schedule service with Mi Amigo Heating & Cooling. Our certified technicians will evaluate your system, measure your home, and help you choose the right solution.

Comfort starts with the right AC Size. Let’s get you the right system!