Start Here If Something Stopped Working
Five situations where you stop reading and act. Everything below this band can wait an hour. These cannot.
My AC stopped working, what should I check first?
Turn the system off at the thermostat, then check your air filter and your breaker. A choked filter or a tripped breaker causes a large share of no-cool calls in San Antonio, and both are safe for you to check yourself.
If the filter is grey and packed, swap it and leave the system off for an hour before restarting, because a frozen coil needs time to thaw. If the breaker tripped, reset it one time only. A breaker that will not hold is reporting a fault, not a nuisance. Leave it off and call (210) 202-0255.
Why does my AC smell like something is burning?
Shut the system off at the thermostat and at the breaker, then call. A burning smell is either dust cooking off a heat exchanger on the first heating run of the season or an electrical fault, and the second one does not wait.
A faint hot-dust smell on the first cold night usually clears within twenty minutes and means nothing. Anything sharp, acrid, or like melting plastic is wiring or a motor, and it should not run another minute. Leave the power off until a technician has been inside the cabinet.
My carbon monoxide alarm went off, what should I do?
Get everyone out of the house first, then call 911 or your gas utility from outside. Do not go back in to investigate, and do not wait to see whether the alarm resets itself.
Carbon monoxide has no color and no smell, so the alarm is the only warning anyone gets. Once the fire department or the utility has cleared the house, we can inspect the furnace, the heat exchanger and the venting to find the source. That inspection is a separate visit from the emergency response.
Why is my AC leaking water inside the house?
Turn the system off at the thermostat. Water indoors almost always means a plugged condensate drain, and every minute it keeps running pushes more water toward your ceiling, your drywall or your flooring.
Gulf humidity plugs condensate lines here faster than in most of the country. A float switch is supposed to shut the system down before the pan overflows, so water on the floor means that switch has failed or was bypassed. Mop what you can reach and leave the system off.
Why does my breaker keep tripping when the AC turns on?
Reset it once. If it trips a second time, leave it off and call. A breaker that keeps going is reporting a short, a failing compressor, or a motor drawing more current than it should.
Repeated resets push current through a fault, and that is how a capacitor replacement becomes a compressor replacement, which is the most expensive part on the system. Our diagnostic is a flat $119 for residential systems, credited toward the repair when you move ahead.
Nothing on fire, but something feels off? Twice-yearly service catches most of this while it is still small. See AC Maintenance & Tune-Ups.
AC Repair
San Antonio runs its air conditioning roughly eight months a year, so this is the section we get asked about most. These are the questions homeowners type in at two in the afternoon in July.
Why is my AC blowing warm air?
Four suspects, in the order we check them: a clogged filter, a dirty outdoor coil, a refrigerant charge that has leaked down, or a failing compressor. The first two you can rule out yourself in ten minutes.
Start with the filter and make sure the outdoor unit is clear of grass and leaves. If both are clean and it still blows warm, the cause is inside the refrigerant circuit and needs gauges. Low charge always means a leak, because refrigerant is a sealed loop that nothing consumes. Topping it up without finding the leak is paying twice for one problem.
Why is my AC freezing up?
Ice on the coil or the copper line means airflow or charge. A blocked filter starves the coil of warm air and it frosts over, and a low refrigerant charge drops the coil below freezing. Both end with ice.
Turn the system off and let it thaw fully, which takes a few hours, then change the filter and check that no returns are blocked by furniture or rugs. If it ices again after that, it is charge, and running it frozen risks slugging liquid refrigerant back into the compressor. That turns a small repair into a large one.
Why is my AC making a loud noise?
The sound tells you the part. Squealing points at a belt or a motor bearing, grinding at bearings that are failing outright, buzzing at an electrical component, and clicking that never starts the unit at a relay or capacitor.
A rattle is often the cheapest thing on the list, a loose panel or debris in the condenser. A metallic grinding is the one to act on the same day, because a seizing motor draws hard and takes other components with it. Tell us the noise when you call and we can usually bring the part.
Should I repair or replace my AC?
Repair when the unit is under about ten years old and one part failed. Price a replacement when it is past twelve to fifteen, the same unit keeps failing, or you are facing a several-thousand-dollar repair.
Those are guides, not a formula, and the answer depends on what failed. A capacitor on a nine-year-old system is a straightforward repair. A compressor on a fourteen-year-old system rarely is. We are repair-first, which means we say so when a repair still makes sense on a system another company has written off, and that happens once or twice most weeks.
How long does an AC unit last in Texas?
Twelve to fifteen years is the usual range for a system that gets serviced. Here it lands at the lower end more often, because our cooling season runs about eight months and runtime is what wears equipment out.
A unit in San Antonio logs far more hours than the same model in a four-month climate, so national lifespan figures run optimistic for us. What moves it back up the range is airflow and charge. A system that spends years running with a dirty coil or a slow leak works harder every hour it runs, and the compressor pays for it.
Why is my electric bill so high in the summer?
Usually the system is running longer than it should for the same comfort. A dirty filter, a leaking duct run, low refrigerant or an oversized unit that short-cycles all push runtime up, and runtime is what you pay for.
Compare this July against last July rather than against June, because the bill tracks the weather more than anything else. If the jump is real, the cheapest checks come first: filter, coil, and whether the ducts in your attic are losing cooled air before it reaches the room. Sealing those is often less than a repair.
Ask about AC Repair when you call, or see AC Maintenance & Tune-Ups to catch these earlier.
AC Installation and Replacement
The questions that come up once repair stops making sense. Replacement is a fifteen-year decision and the sizing matters more than the badge.
How much does it cost to replace an AC unit?
There is no flat price worth quoting, because the number moves with the system you choose, its efficiency, your home's size and the condition of your ductwork. We quote it in writing after a free in-home estimate.
What we can tell you is what changes the figure. Efficiency tier and capacity are the obvious ones. The less obvious ones are whether the ductwork and line set can be reused, whether the electrical needs work, and whether the old equipment needs hauling. A quote that leaves those out is not cheaper, it is incomplete. Financing is available for qualified customers, subject to approval.
What size AC do I need for my house?
It comes from a room-by-room load calculation, not from square footage. The calculation accounts for insulation, window area and orientation, ceiling height, ductwork and how the rooms are used.
Rule-of-thumb sizing is how homes end up oversized, and oversized is the more common fault here. An oversized system cools fast, shuts off early, and never runs long enough to pull humidity out, so the house feels clammy at a temperature that should feel comfortable. The number a load calculation produces is often smaller than homeowners expect.
What SEER2 rating should I buy?
High enough that the runtime pays it back, which in San Antonio is further up the range than in a cooler climate. The jump from base efficiency to a good mid-tier unit usually returns the difference in bills.
Where it stops paying is at the very top. The highest tiers earn their price if you plan to stay in the house a long time, or if you want the humidity control and quieter operation that variable-speed equipment brings. Those are comfort arguments as much as bill arguments. We will show you where the line falls for your house rather than steering you to the biggest number.
Can I replace just the outside unit?
Sometimes, and it is usually a false economy. The outdoor condenser and the indoor coil are matched as a system, so pairing a new condenser with an old coil costs you efficiency and can void the manufacturer's warranty.
There is also a refrigerant problem. Older systems run on refrigerant that is being phased out, and a new condenser will not be designed for it. Where the indoor coil is genuinely recent and compatible, replacing one side can work. We will tell you which situation you are in before quoting, because the matched-system answer is the more expensive one and it should be justified.
When is the best time of year to replace an AC?
Spring or fall, before the season that will break it. Lead times are shorter, scheduling is flexible, and you are deciding with a working system instead of standing in a hot house on a Saturday.
A planned replacement is a better replacement. You get time to compare options, sort financing without pressure, and pick a date that suits you. An emergency replacement in August compresses all of that into an afternoon, which is when people buy the wrong size for the wrong reason. Our quiet months are December, January and February.
Ask about AC Installation & Replacement when you call.
AC Maintenance and Air Filters
The cheapest part of owning a system, and the part most often skipped. Most of the breakdowns we drive to were preventable.
How often should I change my air filter?
Every 30 to 60 days through cooling season, and closer to 30 with pets, allergies or construction nearby. Our long runtime pushes far more air through the filter than a shorter season would.
Basic fiberglass filters load up fastest and need the short end of that range. Pleated filters last longer and catch more. Write the install date on the frame edge, because nobody remembers otherwise, and a choked filter is the single most common cause of the no-cool call we get on the hottest Saturday of the year.
Can a dirty air filter damage my AC?
Yes, and it is the most common self-inflicted damage we see. A blocked filter starves the coil of airflow, which freezes the coil, floods the drain pan and makes the blower and compressor work harder than they were designed to.
The damage is cumulative rather than sudden. Months of restricted airflow shortens compressor life, and a frozen coil that thaws repeatedly can overflow the pan into your ceiling. A filter costs a few dollars. The repairs that follow a neglected one routinely run into the hundreds, and occasionally into a compressor.
What MERV rating should I use?
Match it to what your system can move. A higher MERV catches finer particles and also restricts airflow, and restricted airflow drops capacity and can freeze the coil on equipment that was not designed for it.
Higher filtration is not automatically better. If you want genuinely better air without choking the system, a four- or five-inch media cabinet gives you high filtration across a much larger surface area, so the pressure drop stays manageable. We measure static pressure before recommending one, because the right answer depends on your blower and your ducts.
Can I clean my own AC coils?
The outdoor coil, yes, carefully. Kill the power at the disconnect, then rinse it from the inside out with a garden hose at normal pressure. Never use a pressure washer, which bends the fins flat and makes the problem worse.
The indoor evaporator coil is a different job. It sits inside the air handler, it usually needs panels removed and sometimes the coil pulled, and cleaning it badly can damage the fins or the drain pan. That one is part of a service visit. Keeping two feet of clearance around the outdoor unit does more good than most people expect.
What temperature should I set my thermostat in summer?
Most San Antonio households land between 76 and 78 while they are home, and a few degrees higher while they are out. Every degree you raise it cuts runtime, and runtime is the whole bill.
Setting it far lower does not cool the house faster, because the system moves the same amount of heat either way. It only runs longer. If the house feels warm at 76, the issue is usually humidity rather than temperature, and drier air feels cooler at a higher setpoint. That is a different fix from dropping the thermostat.
See AC Maintenance & Tune-Ups and Maintenance Plans.
Heat Pumps
More San Antonio homes are running one heat pump for both seasons instead of a separate air conditioner and furnace. These are the questions that come up first.
How does a heat pump work?
It is an air conditioner that can run in reverse. The same refrigerant cycle that moves heat out of your house in summer flips direction in winter, through a reversing valve, and moves heat into it instead.
That is why it heats without burning anything. There is no gas burner and no combustion, so there is no carbon monoxide risk from the heating side. One outdoor unit and one indoor air handler cover both seasons, which is also why a heat pump logs far more annual runtime than a cooling-only system does.
Are heat pumps worth it in Texas?
In San Antonio, usually yes. Our climate is cooling-dominated with short winters, which is close to the ideal case for a heat pump, and one system covering both seasons means one thing to maintain instead of two.
The case is strongest when you are replacing an aging air conditioner and furnace at the same time, because you are buying one system instead of two. It is weaker if your furnace is newer and only the AC has failed. We will price a heat pump beside a conventional system so you can compare on paper rather than take our word for it.
Do heat pumps work when it gets below freezing?
Yes. Modern equipment holds useful capacity well below freezing, and San Antonio cold snaps are short. For the handful of hardest nights, backup heat or a dual-fuel setup covers the gap.
The thing that surprises people is the air temperature. A heat pump delivers air around 90 to 95 degrees rather than the 120 or so a furnace produces, so it can feel underwhelming at the vent even while the house holds temperature perfectly. That is the design working, not a fault.
Why did my electric bill spike when the heat pump ran?
Almost always the auxiliary heat strips. Those are electric resistance elements that switch on when the heat pump cannot keep up or when it is defrosting, and they draw a great deal more power than the heat pump itself.
You will see them on the thermostat as AUX or EM HEAT. A short run during a freeze is normal. A bill that jumps means they ran far longer than they should have, and the usual causes are a large thermostat setback that triggers them every morning, a low refrigerant charge, or a failing defrost control. All three are fixable without a new system.
See Heat Pump Installation and Heat Pump Repair.
Ductless Mini-Splits
Ductless earns its place on the room your central system was never sized to reach.
How long does a mini-split last?
Fifteen to twenty years for a system that gets its filters rinsed and its coils cleaned, which is longer than most central equipment manages here. Inverter compressors spend most of their life running at lower speed, and that gentler duty is why.
The caveat is upkeep, and ductless is less forgiving than central. A neglected head runs for years with a fouled blower wheel and a restricted coil, which shortens the compressor the same way a blocked filter shortens a central system. Keep the filters rinsed and the equipment usually outlasts expectations.
How much does it cost to install a mini-split?
It depends mostly on how many zones you need. A single-zone system for one problem room sits at the low end, and a multi-zone system covering several rooms costs considerably more because each head adds equipment and labor.
Capacity, the length of the line set and how the head is mounted all move the number too. We quote it after a free in-home estimate, in writing, before anything is ordered. Where a single zone would solve the problem for less than a whole-home system, we will price that option rather than the larger one.
Can I put a mini-split in just one room?
Yes, and that is the most common reason people install one. A single-zone system runs entirely independently of your central equipment, with its own outdoor unit and its own thermostat.
The usual candidates in San Antonio are a converted garage, a room over the garage, a sunroom, a casita, or an addition the original ductwork never reached. Adding a zone is almost always cheaper than resizing a central system to cover one stubborn space, and it leaves the rest of the house alone.
Do mini-splits need maintenance?
More than people expect. The indoor heads have washable filters that need rinsing every month or two, and the blower wheel inside each head needs periodic cleaning, because there is no large central filter catching things upstream.
Skipped cleaning is the main reason ductless systems develop a musty smell, and once growth establishes on a blower wheel it takes a deep clean to remove. The filters take a few minutes and you can do them yourself. The blower wheel and coil are part of a service visit. In our humidity this matters more than it would in a dry climate.
See Ductless Mini-Split Repair.
Indoor Air Quality and Ductwork
In this climate, comfort is as much about moisture and airflow as it is about temperature.
How do I know if my air ducts are leaking?
The signs are rooms that never match the thermostat, a dusty house no matter how often you clean, and bills climbing while comfort does not. In most San Antonio homes the ducts run through an attic well over 130 degrees in summer, so the losses are expensive.
Guessing is not good enough on this one. A technician confirms it with a pressure test and a visual inspection of the accessible runs, joints and boots. Sealing a leaking run stops the loss at its source, and it is frequently cheaper than the equipment upgrade people reach for first.
Why is my house so humid even with the AC on?
Usually an oversized system. Air conditioning pulls moisture out by running long and slow across a cold coil, so a unit that satisfies the thermostat in eight minutes never gets the time to do it.
Leaky ductwork makes it worse by drawing humid attic air into the system. This is the most common comfort complaint we hear in Gulf-humidity months, and it is why sizing matters more than raw capacity. Two-stage and variable-speed equipment run longer at lower output and wring out far more moisture than single-stage equipment can.
Do I need a dehumidifier in San Antonio?
Often it is the better buy. If your house holds temperature but still feels clammy, you have a moisture problem rather than a cooling problem, and a whole-home dehumidifier addresses it directly.
Drier air feels comfortable at a higher thermostat setting, so the system runs less and the bill usually offsets part of the running cost. We measure indoor humidity and runtime before recommending one, because sometimes the answer is sealing returns so the existing system runs longer, and that costs less.
Why is there so much dust in my house?
Most often a low-grade filter recirculating fine particles, or leaking return ducts pulling attic dust straight into the airflow. Both put the same dust back on your surfaces a day after you clean.
The filter is the cheap test, so start there and move up a grade if your system can move the air. If the dust keeps coming back with a good filter installed, the returns are the likely path, and that is a duct inspection rather than an air-quality product. Fixing the leak solves what a purifier only masks.
See Indoor Air Quality.
Heating and Furnaces
A short season here, which is exactly why it catches people out. A system idle for eight months has to work on the coldest night of the year.
Why is my heater blowing cold air?
On a furnace, the usual causes are a dirty flame sensor, a weak igniter, or a lockout after a failed ignition attempt. The blower runs, the burner does not, and you get room-temperature air.
Check the thermostat is on HEAT and the filter is clean, then stop there. Everything past that point is gas and combustion, which is licensed work for good reason. A furnace that tries to light and fails repeatedly will lock itself out deliberately, and resetting it over and over without fixing the cause is how a cheap flame sensor becomes a bigger repair.
How long does a furnace last?
Fifteen to twenty years, and often longer here, because a San Antonio furnace runs a fraction of the hours one in a cold climate does. Age alone is a weaker replacement signal on heating equipment in this market.
What ages a lightly used furnace is sitting still rather than running. Rodents get into cabinets, capacitors dry out, flame sensors foul and rust forms in venting. We look at the heat exchanger, the venting and the controls rather than the date on the label. A nineteen-year-old furnace in good condition is not automatically a replacement.
Why does my furnace smell like dust when I turn it on?
Because dust settled on the heat exchanger over eight months of not running, and the first heating cycle burns it off. It is normal and it usually clears within twenty minutes.
Run the heat for a short cycle on a mild evening in late October rather than meeting that smell on the first freezing night. If it lasts beyond half an hour, returns every cycle, or turns sharp rather than dusty, that is no longer settled dust and it is worth a look. Changing the filter before the first run helps.
Should I leave the heat on when I am not home?
Setting it back while you are out costs less. A house loses heat faster the bigger the gap between inside and outside, so a cooler house all day loses less overall.
The worry that the system works harder catching up, and cancels the saving, does not hold for a gas furnace. For a heat pump keep the setback smaller, around three or four degrees, because a large recovery can bring on the auxiliary heat strips and those are expensive to run. A programmable thermostat handles the difference without you thinking about it.
What should I do before the first freeze in San Antonio?
Run the heat for ten minutes in mild weather in late October, change the filter, and clear anything stored against the indoor unit. If it lights, holds and smells like nothing after twenty minutes, you are set.
This is the cheapest item on this page and the most often skipped. The first hard freeze is when every HVAC company in Bexar County is triaging calls at once, and a furnace that has not run since March is the most likely one to fail. A fall tune-up covers this properly and gets it scheduled for you.
See Heating Contractor.
Costs, Quotes and Choosing a Contractor
Pricing gets the vaguest answers in this trade. Here is how to read a quote, ours included.
Why are HVAC quotes so different from each other?
Because they are usually not quoting the same job. Equipment tier, whether the ductwork and line set get addressed, whether a load calculation was done, permits, commissioning and the labor warranty all move the number more than the badge does.
Compare line items rather than totals. The cheaper quote often has the same condenser and none of the work around it, and that work is what decides whether the system reaches year fifteen. Bring a competing quote to us and we will go through it with you line by line.
What should be included in an HVAC quote?
The load calculation result, specific equipment model numbers, what happens to the ductwork and line set, the permit, commissioning, the labor warranty term with its conditions, the total, and the payment schedule. In writing, before anything is ordered.
A model number and a price is not a proposal, it is a guess with a total attached. Warranty conditions matter as much as warranty length. Ours covers repair labor for up to 10 years on systems we install, and it holds on the condition that the system stays maintained and that nobody else services it.
How do I check if an HVAC contractor is licensed in Texas?
Look the license number up on the Texas Department of Licensing and Regulation website, and confirm the name on the license matches the name on your quote. A number printed on a truck proves nothing by itself.
Ours is TACLB 110532E, and our technicians hold EPA-608 certification for refrigerant handling. Ask any contractor for the number in writing before work starts, along with proof of insurance. Hesitation on either question tells you something more useful than the answer would have.
Is a second opinion worth getting on a replacement quote?
On a replacement, almost always. It costs one appointment and it regularly changes the outcome, because a meaningful share of systems quoted for replacement turn out to be repairable.
We see it once or twice most weeks. A homeowner is told the system is finished, a correct diagnosis finds one failed part, and the repair runs a fraction of the replacement. Bring the other quote with you. If replacement genuinely is the better call, you will see why, and you will have two numbers to weigh instead of one.
