It's one of the most common AC repair calls we get from homeowners in San Marcos — the system is on, air is moving, but nothing coming out of the vents is cold.

Nine times out of ten it comes down to one of three things:

• Low AC refrigerant: There's a leak somewhere in the system. Topping it off without finding the leak just means you pay for it twice.
• A frozen evaporator coil in your AC: Restricted airflow lets the coil ice over, which stops heat transfer completely. Usually traces back to a filter that went too long between changes.
• A failing capacitor or contactor in your AC system: The compressor never fully starts, so the fan blows but nothing gets cooled. Inexpensive part — the damage comes from running the system that way for weeks.

We diagnose the whole system rather than the first fault we find, and you get photos and video of what we found before anyone quotes you. Call (512) 2-RESCUE for same or next-day service in San Marcos.

The honest answer is that it depends on the failure — but what it costs to find out is something you can know upfront.

Here's how pricing works for San Marcos homeowners:

• $70 diagnostic: That covers a full HVAC system evaluation, not just the obvious fault — and it's applied toward the repair if you go ahead with it.
• Three options, always: You get a HVAC repair, mid-range and replacement pricing side by side with the numbers behind each, instead of one take-it-or-leave-it quote.
• Financing available on larger HVAC jobs: 0% APR with no payments for 18 months on qualifying systems, so a failed compressor in July doesn't have to be paid for in July.

Nothing happens without your approval, and you see photos of the problem before you decide anything. Call (512) 2-RESCUE to book a diagnostic in San Marcos.

Most San Marcos homeowners ask this the moment a repair quote crosses about a thousand dollars, and it's exactly the right question to ask.

Three things decide it:

• The age of the AC system: Under ten years, repair almost always wins. Past fifteen, you're usually paying to keep a system alive that's about to cost you again.
• The refrigerant it runs on: Older systems still on R-22 are expensive to recharge — that refrigerant is no longer manufactured, and the price reflects it.
• Repair cost against replacement: When a single repair approaches a third of the cost of a new system, replacement usually wins over a five-year horizon.

We'll run those numbers on your actual system rather than a rule of thumb, and we'll tell you plainly when repairing is the smarter call. Book an evaluation in San Marcos at (512) 2-RESCUE.

Central Texas is harder on cooling equipment than most of the country. A manufacturer's "once a year" assumes a milder climate than San Marcos actually has.

What we recommend for homeowners here:

• Twice a year: Cooling service in spring before the load arrives, heating check in fall. Most of the failures we see in July were already visible in April.
• Filters every one to three months: Sooner with pets or during cedar season. A restricted filter is the single most common cause of a frozen coil.
• Keep the condenser clear: Two feet of clearance and rinse the debris out. Tree cover and pollen load up a coil faster than most people expect.

Our maintenance plan covers both visits, priority scheduling, and a written record of your system's condition over time. Ask about it when you call (512) 2-RESCUE.

Heating season is short in San Marcos, which is exactly why problems go unnoticed until the first real cold snap arrives.

The usual causes, in the order we tend to find them:

• A heat pump in defrost: Heat pumps periodically run a defrost cycle and blow cooler air for a few minutes. That's normal — unless it's happening constantly.
• The thermostat set to "on" instead of "auto": The fan runs continuously, so it keeps blowing between heating cycles. Simplest fix on this list.
• Ignition or flame sensor failure: On a gas furnace a dirty flame sensor shuts the burner down as a safety measure while the blower keeps running. Common after a system has sat unused for months.

A hard freeze is the worst possible time to discover any of this, which is why we check heating in the fall rather than in January. Call (512) 2-RESCUE for heating service in San Marcos.

We're called Air Responders for a reason. In a Texas summer, losing your AC isn't an inconvenience — it's an emergency, and we built the company to treat it like one.

What that means on a San Marcos service call:

• You get professional HVAC support: You get a professional HVAC pro on the phone, then a text with your technician's photo, name and arrival window — and you can track them on the way.
• We evaluate the whole HVAC system: Every visit includes a full HVAC evaluation with photos and video of what we found, not a verbal diagnosis of the one part that failed.
• Your home gets protected during the HVAC job Shoe covers, drop cloths and gloves as standard, and a manager calls after every job to check the work held up.

We also look after the first responders this company is named for — ask about our first responder offer when you call (512) 2-RESCUE.