When your system finally gives out — usually on the hottest afternoon of the year — the temptation is to call and say put in the biggest unit you have. It makes sense, and it is almost always the wrong move. An air conditioner that is too big will keep your house less comfortable than one sized right. Here is what really matters when you buy a new AC in Abilene.
Why bigger is not better
Your AC does two jobs on a West Texas afternoon: it cools the air, and it pulls the humidity out of it. An oversized unit cools the air so fast that it shuts off before it ever gets to the second job. You end up with a house that feels cold and clammy, a system that clicks on and off all day — we call it short-cycling — and parts that wear out early.
Undersized is the other ditch. A unit that is too small runs without stopping and still cannot catch up when it hits 104°. The goal is the size that is right for your house, and the only way to know that is to measure.
The right way: a load calculation
A good installer does not guess your size off square footage alone. They run a load calculation — the trade calls it a Manual J — that accounts for the things that decide how hard your system has to work:
- Square footage and ceiling height
- Insulation and how tight the house is
- The number, size, and direction of your windows — west-facing glass in Abilene is brutal
- The condition and layout of your ductwork
- Shade, or the lack of it
You will hear a rule of thumb like one ton for every 400 to 600 square feet. That is a rough starting point, not an answer. An older Abilene home with single-pane windows and thin attic insulation needs a very different system than a tight new build of the same size.
What SEER2 means for your bill
Every new system carries a SEER2 rating — think of it as miles per gallon for an air conditioner. The higher the number, the less electricity it burns to do the same cooling. As of January 1, 2023, the federal minimum for our region — the South, which includes Texas — is 14.3 SEER2, which is roughly the old 15 SEER, for most home-sized systems.
A higher-efficiency unit costs more up front and less every month. In a place where the AC runs a big part of the year, stepping up in efficiency often pays for itself over the life of the system. We will show you the trade-off honestly and let you make the call.
An air conditioner is not one box — it is an outdoor unit, an indoor coil, and a blower, all working together. Putting a new outdoor unit on an old, mismatched coil is a common shortcut that leaves you with a system that never reaches its rated efficiency and tends to fail early. A proper replacement matches the components, and a good installer will tell you what refrigerant your new system uses, since the rules on that changed in 2025.
Do not forget the ductwork
None of it matters if your ducts cannot move the air. If they are leaky, crushed, or too small, you lose the performance you paid for. That is why we check the ductwork before we ever quote a system.
What to ask any installer — including us
- Did you run a load calculation, or are you sizing off square footage?
- Is the whole system matched — outdoor unit, coil, and blower?
- What is the SEER2, and what will the higher-efficiency option save me?
- Is my existing ductwork the right size and in good shape?
- What does the warranty cover, and who services it after it is in?
Why homeowners let Hawkins size it
We have been putting systems in Abilene homes since 1976. We are Carrier Factory Authorized, we size the system to your actual house, and we install it clean — then we are here to service it for years, with the same crew. If the cost of a full system is the sticky part, financing is available through First Financial Bank, and a maintenance plan keeps the new one healthy. When you are ready, we will take a look and tell you what it will cost before we touch a thing. See AC installation and replacement.
Written by the Hawkins Air Conditioning team — family-run in Abilene since 1976. Questions? Call or text (325) 692-3645.



