No cooling
The system runs, but the home stays warm or never reaches the thermostat setting.
Owner-led HVAC serviceSan Antonio, TexasTACLB00102161E
AC & heating repair · San Antonio
A diagnosis you can understand.
When your AC or heater is not working correctly, Arthur traces the problem, explains the evidence, and reviews practical repair options with you before approved work begins.
25+ years in HVACEnglish / EspañolOwner-led service
Diagnostic starting point$89 inside Loop 1604
$119 outside Loop 1604. The diagnostic fee applies toward an approved repair.
Clear findings✦Options before approval✦Practical repair-first thinking✦Local San Antonio experience
Start with the symptom
Air conditioning and heating problems we diagnose.
One symptom can have several causes. A service visit tests what the system is actually doing so the recommendation follows evidence instead of guesswork.
Warm air
Room-temperature or warm air comes from the vents during a cooling call.
Weak airflow
Some rooms feel uncomfortable or air barely moves through the registers.
Short cycling
The equipment starts and stops repeatedly instead of completing a normal cycle.
New noises
Buzzing, rattling, grinding, squealing, or other sounds begin during operation.
Water or ice
Water appears near the indoor unit, or ice forms on the coil or refrigerant line.
Power trouble
The outdoor unit will not start, the system loses power, or a breaker trips.
Heating trouble
The heater blows cool air, cannot reach the setting, or shuts down unexpectedly.
Safety first: If you smell gas, see smoke, hear electrical arcing, or suspect a carbon-monoxide issue, leave the affected area and contact the appropriate emergency or utility service. Do not continue operating the equipment.
Evidence before options
What an HVAC diagnosis may include.
The exact testing depends on the equipment and complaint. The goal is not to overwhelm you with readings—it is to use those readings to reach a supported conclusion.
- 1Thermostat command and control signal
- 2Electrical power, wiring, and safety controls
- 3Filter, blower, coil, return, and supply airflow
- 4Indoor and outdoor equipment operation
- 5Temperature and system performance
- 6Refrigerant-circuit performance when applicable
- 7Condensate drainage and float-switch operation
- 8Heating components, ignition, venting, and safeties
A clear service path
What happens after you contact Air Valentine.
Tell us what is happening
Share the main symptom, whether the system is completely off or still operating, and the best way to contact you.
We test the system
The symptom guides the assessment, but measurements and operating evidence—not a guess—support the diagnosis.
See what we found
Arthur explains what is not operating correctly, the evidence behind that conclusion, and any connected concerns.
Review practical options
You see the repair scope, intended result, and price before choosing how to move forward.
Approve the work
No repair begins until the scope has been explained and you authorize the selected option.
Verify operation
After approved work is completed, the affected system operation is checked again.
Common repair categories
Repair the cause—not just the complaint.
These are examples of work a diagnosis may lead to, not a diagnosis of any specific system. Arthur will explain which category applies and why.
Electrical & controls
- Capacitors
- Contactors and relays
- Low-voltage wiring
- Thermostats
- Control boards
- Safety switches
Airflow & drainage
- Blower motors
- Blower controls
- Filter and return restrictions
- Indoor coil restrictions
- Duct concerns
- Condensate shutdowns
Cooling system
- Outdoor fan motors
- Compressor starting components
- Refrigerant-circuit diagnosis
- Metering concerns
- Coil leaks or damage
- Drain-line issues
Heating system
- Electric heat components
- Heat-pump controls
- Defrost components
- Ignition controls
- Flame sensors
- Inducer or blower problems
Meet Arthur Lozano
Repair first when repair makes sense.
A system does not need replacement simply because it has a problem. Arthur considers the failed component, equipment condition, repair history, comfort performance, part availability, and cost before explaining the practical paths forward.
Replacement deserves discussion when repeated major failures, deteriorating components, obsolete parts, or persistent comfort issues change the value of another repair—not as an automatic answer to every service call.
Since 1998 hands-on HVAC workOwner-led explanations and optionsLocal San Antonio service
Air Valentine answers
What should a clear HVAC diagnosis tell you?
Learn what a technician may test, which questions you can ask, and how the evidence should connect to a repair recommendation.
Repair questions
Answers before the service visit.
Can you diagnose my AC from the symptom alone?
No. A symptom helps narrow the possibilities, but several failures can create the same complaint. Testing is needed before a reliable repair recommendation can be made.
Why is my AC running but not cooling?
Possible causes include an airflow restriction, failed indoor or outdoor component, control problem, refrigerant-circuit issue, or equipment that is operating without producing its expected capacity. Testing determines which cause applies.
Why does my AC keep freezing?
A frozen system may involve restricted airflow, a dirty indoor coil, a blower problem, a refrigerant-circuit issue, or another operating condition. Turn cooling mode off and request service rather than continuing to run a frozen system.
Why is the outdoor AC unit not running?
Possible causes include a power issue, control-signal problem, failed capacitor, contactor, motor, safety control, wiring issue, or compressor-related fault. Do not repeatedly reset a breaker that continues to trip.
Why is my heater blowing cool air?
Heat-pump air can feel cooler than gas-furnace air while still heating normally. Truly cold air or a home that is not warming may point to a thermostat, heat-pump, electric-heat, airflow, ignition, or control problem.
Will I see the price before the repair begins?
Air Valentine explains the diagnosis, repair scope, and price before approved work begins, so you can make the decision with the relevant information in front of you.
Request AC or heating repair
Tell Arthur what your system is doing.
Use the service request form to describe the symptom, choose your urgency, and provide the best way to contact you.