HVAC Repair Desk
Independent heating & cooling guides

When the house is too hot, or too cold.

HVAC Repair Desk is a library of 56 guides on air conditioners, furnaces, heat pumps, and the thermostats that run them. Each one is written so you can tell a five-minute fix from a real service call, and know which jobs are safe to do yourself.

Browse every guideNew to all this? Start with what HVAC means

AC not cooling right now?

Four checks to run before you call anyone.

  1. Check the thermostat

    Set it to Cool and a few degrees below the room. A blank screen usually means dead batteries, and a dead thermostat never calls for cooling.

  2. Check the breaker

    An AC that clicks but will not start, or does nothing at all, often sits behind a tripped breaker. Reset it once. If it trips again, leave it.

  3. Check the filter

    A filter clogged solid chokes airflow until barely any cold air moves. Pull it, hold it to the light, and replace it if you cannot see through it.

  4. Look for ice on the line

    Frost on the copper refrigerant line means the system is freezing up. Turn it off at the thermostat and let it thaw fully before running it again.

If all four check out, or the line keeps icing over, it is a refrigerant or electrical fault and a job for a licensed technician.

Read the full AC not cooling guide

Browse by topic

Every guide sits in one of 5 topics. Start with whatever is wrong today.

Repairs

Warm air, no start, short cycling, odd smells. Read the symptom, then decide who fixes it.

15 guides →

Emergency HVAC

No cooling in a heat wave or no heat in a freeze, and what to do in the first hour.

1 guide →

Maintenance & Service

Filters, coils, and tune-ups. The cheap habits that head off the expensive breakdown.

7 guides →

Installation & Replacement

Sizing, efficiency, and real install costs to weigh before you sign a quote.

32 guides →

Indoor Air Quality

1 guide →

Recently added

Questions we hear most

Should I turn off my AC if it's leaking water?

Yes, in most indoor cases. Set the thermostat to Off if water is on a finished floor, running down a wall, or coming through a ceiling, and shut the breaker if water is near the electrical whip or the blower. The one exception is a coil that has iced over: switch cooling Off but leave the fan On so the ice thaws faster. Water on the outdoor pad needs no action at all.

How much land do you need for geothermal heating and cooling?

A horizontal loop for a whole house usually needs a quarter acre or more of clear, diggable ground, kept clear of the septic field, well head, buried utilities, and mature tree roots. A vertical borehole field needs far less surface area, often just a few bores spaced roughly 20 feet apart, which is why small lots almost always end up vertical.

Is a whole house dehumidifier worth it?

It's worth it when the whole home reads above 55 percent for weeks at a time, the dampness spans multiple floors, and the AC already runs long cycles. If one room is damp, a portable does the same job for far less.

Does homeowners insurance cover HVAC replacement?

Only when a covered peril broke it. Fire, lightning, hail, windstorm, a falling tree, vandalism, and theft are the usual ones, and the claim is subject to your deductible. A system that simply wore out, seized, or stopped cooling after ten or fifteen years is excluded under the wear and tear clause of every standard policy. Adding an equipment breakdown endorsement closes part of that gap by covering sudden mechanical or electrical failure, but it still will not pay for gradual deterioration or neglect.

What qualifies as an AC emergency?

No cooling during extreme heat, a burning or electrical smell, a refrigerant leak, water pooling near the indoor unit, or a breaker that trips repeatedly all qualify. A system that still cools but runs louder than usual can typically wait for a scheduled appointment.