AC Troubleshooting Guides for Washington DCsafe checks before you call

The warm air guide walks through thermostat, filter and outdoor unit checks. The frozen coil guide explains why ice forms in summer and how to thaw safely. The won't-turn-on guide covers thermostats, breakers, disconnects and safety switches.

The leaking water guide explains condensate drains, pumps and pans, and how to limit damage. The short cycling guide covers sizing, thermostat placement and the faults that make systems start and stop too often.

These are general guides for DC homes. They do not replace a technician who has seen your system, and none of them involve opening electrical panels or handling refrigerant. Each lists its sources.

Start with the guide that matches what you see. If more than one applies, such as ice and water together, read both, since one problem often causes the other. The guides link to the service pages that explain repairs in depth.

Every check in these guides is something a homeowner or renter can do without tools or special training, such as reading a thermostat, changing a filter, resetting a breaker once or looking at the outdoor fan. Anything beyond that belongs to a licensed technician. When in doubt, switch the system off and call.