Emergency and Troubleshooting

AC Not Cooling: What to Check Right Now

Six checks you can make safely in ten minutes, a plain reading of what each one tells you, and a clear line for when to stop and call. No panels, no ladders, no guesswork.

Warm Air Diagnosis

AC Blowing Warm Air

The blower works. The air does not. Here is how to tell a thermostat setting from a dead outdoor unit, and a dirty coil from a refrigerant leak, before you spend a dollar.

Nonstop Runtime

AC Running but the House Is Hot

The system has not shut off since noon and the thermostat will not budge. Sometimes that is Phoenix. Sometimes it is a problem. Here is how to tell the two apart.

Ice in July

Frozen Evaporator Coil

A block of ice inside an air handler on a 110-degree day is not a paradox. It is a symptom. Here is the safe thaw procedure, the three causes, and the reason you should not let it happen twice.

Emergency Symptom Guide

Refrigerant Leak Signs: What the Hiss, the Ice, and the Oil Are Telling You

A sealed system does not use refrigerant up. If yours is low, it leaked, and the only real question is where. Here is how to read the signs before you call.

Emergency Symptom Guide

Compressor Failure: The Diagnosis Everyone Fears and Most Do Not Have

The compressor is the heart of the outdoor unit and the most expensive part in it. It is also blamed for more failures than it commits. Here is how to tell.

Emergency Symptom Guide

Capacitor Failure: The Most Common Way a Phoenix AC Quits in July

A part the size of a soda can starts your fan and compressor a dozen times a day. When it gives out, the unit hums and nothing moves. Do not touch it. Here is what to do instead.

Emergency Symptom Guide

Contactor Failure: When the Outdoor Unit Will Not Start, or Will Not Stop

The contactor is the switch that turns your outdoor unit on and off thousands of times a summer. It fails in two opposite directions, and one of them keeps running after you have told it to quit.

Water Where It Shouldn't Be

AC Condensate Leak and Water Damage

A puddle under the air handler or a spreading ring on the ceiling is a ten-minute problem before it becomes a drywall problem. Here is what to do in the next hour, and what to leave to a technician.

Dark Screen, Dead Air

Thermostat Blank or Unresponsive

A dark thermostat is the one HVAC symptom that is usually not the thermostat. Work through the power chain before you buy anything.

One Reset. That's It.

AC Breaker Keeps Tripping

A breaker that trips once may be a bad afternoon. A breaker that trips twice is a fault report. Here is the one thing to do, and the reasons not to do it again.

A Field Guide By Sound

Noisy AC: Buzzing, Screeching, Rattling, Clicking

Noise is the system telling you where it hurts. Sort the sound, note the location, and you will know whether to shut it off now or mention it at the next tune-up.

Emergency AC Help

AC Short Cycling: Starting and Stopping Every Few Minutes

An air conditioner that runs in short bursts is telling you something, and it is rarely good news for the compressor. Here is what to check safely, what it usually means, and when to stop guessing.

Emergency AC Help

Sudden High Electric Bill From Your AC

Before you blame the air conditioner, find out whether the bill went up or the usage did. The two have different fixes, and only one of them needs a technician.

Comfort Emergency

Uneven Temperatures From Room to Room

The equipment is probably fine. The delivery system is not. Here is how to tell the difference before anyone sells you a bigger air conditioner.

Emergency AC Help

Weak or Bad Airflow From the Vents

Cold air that will not leave the register is as useless as no cold air at all. Most causes are cheap. A few are not. Here is how to tell which you have.

Heat Emergency Safety

When the AC Fails During a Heat Warning

A dead air conditioner in July is a repair problem. A dead air conditioner in July with a grandmother in the back bedroom is a safety problem. Handle the second one first.

AC Not Cooling: What to Check Right Now

AC Blowing Warm Air

AC Running but the House Is Hot

Frozen Evaporator Coil

Refrigerant Leak Signs: What the Hiss, the Ice, and the Oil Are Telling You

Compressor Failure: The Diagnosis Everyone Fears and Most Do Not Have

Capacitor Failure: The Most Common Way a Phoenix AC Quits in July

Contactor Failure: When the Outdoor Unit Will Not Start, or Will Not Stop

AC Condensate Leak and Water Damage

Thermostat Blank or Unresponsive

AC Breaker Keeps Tripping

Noisy AC: Buzzing, Screeching, Rattling, Clicking

AC Short Cycling: Starting and Stopping Every Few Minutes

Sudden High Electric Bill From Your AC

Uneven Temperatures From Room to Room

Weak or Bad Airflow From the Vents

When the AC Fails During a Heat Warning

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