How Glendora homeowners can prep their HVAC system for summer

A quick May checklist for getting your AC ready before the San Gabriel Valley turns triple-digit. The same things we'd do at our own houses — including the one item most homeowners skip every year.

If you live in Glendora, Covina, San Dimas, La Verne, or anywhere else in the San Gabriel Valley, you already know what May means: the foothill heat is showing up earlier every year, June is going to be hotter than it used to be, and August is going to be the kind of week your AC really earns its keep.

We’ve been the HVAC family here since 1979. Every May we get the same question from neighbors — “what should I actually do before summer hits?” This is that list, in priority order, written exactly the way we’d say it standing in your driveway.

Why a May checklist matters more here than most places

The San Gabriel Valley is a cooling-heavy climate. Long summers, hot afternoons trapped against the foothills, and warm nights mean your AC runs more hours per year than systems in cooler parts of the country. Without proper prep, even a well-maintained system can stumble during the worst week of August — and that’s the week we get a hundred phone calls a day and can’t answer all of them same-day.

Preventative maintenance reliably:

• Restores cooling performance to factory spec
• Cuts unexpected breakdowns by roughly two-thirds
• Lowers cooling costs 10–25% on a system that had drifted
• Extends the useful life of equipment by 3–5 years
• Keeps the air your family breathes cleaner

The five-step Glendora homeowner prep list

1. Replace your air filter (today, not later)

Cheap, fast, and the single highest-ROI thing you can do this month. A dirty filter chokes airflow, ices up the indoor coil, and forces the system into long miserable cycles that age every other component. Most filters need replacement every 1–3 months — more often if you have pets or live in a windy/dusty part of the valley.

2. Clear the area around your outdoor unit

Walk out there right now. Look at the condenser. Pull off anything stuck to the coil — leaves, palm shavings, cottonwood, dryer lint, plastic bags. Give it 18–24 inches of breathing room on every side. Trim any plants that have crept in over the winter. Hose the fins gently from outside the unit (with the breaker off).

“The outdoor unit’s entire job is to dump heat into the air. Anything blocking it costs you efficiency — and parts.”

3. Test the thermostat before you actually need it

Set it to Cool, drop it five degrees, and listen. The outdoor unit should kick on within a minute, and you should feel cold air at the registers within five. If anything about that sequence is off — long delay, no response, weak air — you’ve found a problem now, in May, with our schedule wide open.

If you’re still on a 15-year-old beige rectangle, this is also a great moment to look at a smart thermostat. The right one pays for itself in a Southern California summer through scheduling alone — plus remote control, occupancy sensing, and SCE rebate eligibility.

4. Pay attention to airflow at every vent

Walk the house. Hold your hand under each register. They should all feel about the same. Significantly weaker airflow at one or two vents typically means:

• A crushed or disconnected duct in the attic
• Closed or partially blocked vents (rugs, furniture)
• A leaky duct system bleeding conditioned air into the attic
• Undersized return air for the home

None of these get better on their own. Catching them in May means fixing them with the AC still working — not after a failure.

5. Book a professional tune-up

A real AC tune-up is what closes the loop on everything above. A licensed tech with the right tools will:

• Measure refrigerant pressure and superheat/subcool (the real test of system health)
• Test the run capacitor under load — the #1 mid-summer failure
• Deep-clean the outdoor coil with proper coil cleaner, not just water
• Check and tighten every electrical connection
• Flush the condensate line so you don’t flood a hallway in July
• Calibrate the thermostat and measure airflow at the plenum

$189 for non-members, $129 for returning customers, free for Comfort Club members. The single best HVAC dollar you spend each year.

Why hiring a local Glendora HVAC company actually matters

Anyone with a van and a license can change a filter. Knowing how a 1962 ranch in north Glendora behaves in a heat dome — or which Covina neighborhoods have the worst attic duct runs, or what brands the original tract builders installed in San Dimas in the 1980s — only comes from being here, in this valley, for forty-five years.

We answer the phone with a real human. We don’t hand off your job to whichever subcontractor is closest. We’ve been inside more San Gabriel Valley homes than just about anyone in the business, and we’d rather help you in May than triage you in August.