Vent: heating and cooling troubleshooters
Air conditioners, furnaces, heat pumps and thermostats. Pick the symptom, answer a few questions at the thermostat or the unit, and find out what you can fix today and what needs a licensed technician.
No match here. Try fewer words, or search all three systems.
- AC running but blowing warm air
- AC won't turn on, or the outdoor unit isn't running
- Ice on your AC lines or coil
- AC leaking water inside the house
- Furnace blowing cold air instead of heat
- Furnace clicking but won't ignite
- Furnace keeps turning on and off
- Thermostat screen is blank
- Weak airflow from vents, or one room hotter or colder than the rest
- Heat pump not heating, or blowing cool air
What this section will and won't tell you to do
Nothing here involves refrigerant, capacitors, burners or flame sensors. Those are technician jobs by law or by good sense, and every result says so when you reach one.
Leave or call right away if you notice
- You smell gas or rotten eggs, or hear hissing or blowing near a gas line or the meter.Leave the building now and take everyone with you. Don't flip switches, use appliances or use a phone inside. Call 911 or your gas utility once you're well away from the house.
- A carbon monoxide alarm is going off.Get everyone outside, then call 911. Don't go back in until responders say it's safe.
- People in the house have headaches, dizziness, weakness, nausea, chest pain or confusion, especially when the heat is running.Get everyone outside to fresh air, then call 911.
- A burning, metallic or chemical smell from the furnace, or soot around the furnace or its vents.Shut off the furnace, ventilate the house, and call an HVAC technician. If a CO alarm sounds or anyone feels sick, get outside and call 911.