Why twice a year makes sense on the Gulf Coast
In a mild climate an annual visit is fine. Houston is not mild. The cooling season is long, the humidity load is heavy, and pollen in spring plus grass clippings all summer coat the outdoor coil.
We prefer spring and fall. Spring catches the system before the first triple digit week, which is when neglected equipment fails. Fall checks the heating side and clears out what summer left behind. If you can only do one visit a year, make it spring.
What we are actually doing out there
The outdoor coil gets washed. A coil packed with cottonwood, dust and grass cannot dump heat, so head pressure climbs, the compressor works harder, and cooling capacity quietly drops. This is the highest value item on the list.
The condensate drain gets flushed and the safety switch gets tested. In this climate the drain line is the most common reason a healthy system shuts itself off. We would rather clear it in April than answer your call in July.
Electrical components get measured, not eyeballed. The run capacitor is read against its rated microfarads, contacts are inspected, connections are tightened, and amp draw is compared to the nameplate. A capacitor drifting out of tolerance is a few dollars in spring and a ruined weekend in August.
What maintenance does not do
It does not make an old system new. A twelve year old compressor is still twelve years old after a tune up, and it does not guarantee nothing will break, because parts sometimes fail without warning.
What it removes are the predictable failures: dirt, clogs, drift and loose connections. A clean, correctly charged system with good airflow uses less energy than a dirty, starved one, and tends to last longer. We will not attach a percentage to that, because the honest number depends on how bad the starting condition was.
What you can do between visits
Change the filter on a schedule you will actually keep. With pets or an ongoing remodel, that is more often than the box suggests. A restricted filter starves airflow, which freezes coils and kills blower motors.
Keep two feet of clear space around the outdoor unit. Trim the shrubs back and do not stack anything on top of it. With the power off at the disconnect you can rinse the fins gently with a garden hose from the inside out. Low pressure only, because a pressure washer folds the fins flat and makes the problem permanent.
What a maintenance visit covers
- Condenser coilWash out the debris that keeps the outdoor unit from rejecting heat.
- Condensate systemFlush the drain line, clean the pan and test the float switch.
- Capacitor and contactorRead the capacitor against its rating and inspect the contactor for burned contacts.
- Refrigerant chargeVerify the charge by measurement and note any sign of a leak rather than topping off.
- Airflow and blowerCheck the filter, blower wheel and temperature split across the indoor coil.
- Connections and amp drawTighten electrical connections and compare motor amp draw against the nameplate.