What to do when heating or cooling stops
When the heat or the cooling stops, the useful first step is to separate a danger from a setting. This guide is that split. It does not tell you to open a refrigerant circuit, light a furnace, or buy a new system. The independent technician who sees the equipment decides what failed. Dial Home Help does not employ that technician and does not name a repair price.
Leave if it is dangerous
If you smell gas, leave the house and call the gas utility or 911 from outside. Do not hunt for the source with a lighter or by turning switches on and off in a room that smells of gas. If a carbon monoxide alarm is sounding, get everyone out and call 911. Do not treat either case as a thermostat problem.
If the equipment or the floor around it is wet, do not touch it. Ready.gov's warning about wet electrical equipment applies here. Water and a blower or a panel are a reason to stop, not a reason to reset a breaker.
Checks that do not open the unit
Confirm the thermostat is set to heat or to cool, not to off, and that the setpoint is actually beyond the room temperature. Replace thermostat batteries if the screen is blank and the thermostat uses them. Look at the air filter only if you can slide it out without tools. A filter packed solid can stop airflow. The U.S. Department of Energy's Energy Saver pages describe filters and system care as maintenance, not as a diagnosis of a dead compressor or a cracked heat exchanger.
You may reset a breaker once if the panel is dry, there is no burning smell, and the breaker is clearly the one for the air handler or the condenser. If it trips again, leave it off and call. Repeated resets are how a fault becomes a fire. Do not remove panels to look at wiring.
Refrigerant is not a homeowner adjustment
EPA Section 608 requires certification for technicians who maintain, service, repair, or dispose of equipment that could release controlled refrigerants. Adding refrigerant, recovering it, or opening the sealed circuit is that work. Do not buy a can and connect it because a gauge in a video said the system was low. A low charge is often a leak, and the leak is the repair.
Ask the technician whether they hold a Section 608 certification before they discuss refrigerant. Dial Home Help does not check the card on this website. You can ask to see it at the house.
Repair, or a different system
Ask for the failed part in writing, whether the quote is a repair of that part, and what they did not inspect. A no-heat call is not automatically a replacement. Energy Saver explains how heating and cooling equipment uses energy. It does not set the price of your repair, and neither do we. ENERGY STAR labels matter when you are choosing new equipment, not when you are deciding whether tonight's failure is a capacitor, a filter, or a heat exchanger.
If the outage is the whole neighborhood, the guide on what to do when part of the house loses power is the closer match. If only the air handler is dead and the lights are on, stay on this page. Say which of those you see when you call.
Steps
- Rule out gas and carbon monoxide. Leave and call 911 or the gas utility from outside if you smell gas or a carbon monoxide alarm is sounding.
- Check the thermostat and the filter. Mode, setpoint, batteries, and a filter you can remove without tools. Do not open sealed panels.
- Reset a dry breaker only once. If it trips again, or if you smell burning, stop. Do not reset a wet panel.
- Do not add refrigerant. EPA Section 608 certification applies to technicians who handle refrigerant. A low charge is a technician's diagnosis.
- Ask for the failed part in writing. Repair of a named part is not the same quote as replacement of the system. The provider sets the price.
Questions
Can I recharge the air conditioner myself?
No. Opening the refrigerant circuit is technician work covered by EPA Section 608 certification. A low charge often means a leak.
Does a stopped system mean I should replace it?
Not from this page. Ask what failed. A filter, a thermostat, or a single part is not automatically a new system.
Who sets the price?
The independent provider who sees the equipment. Dial Home Help does not quote repairs and does not do the work. The provider may pay Dial Home Help.
What if the whole house has no power?
Treat that as an electrical outage, not as a failed air conditioner. Do not reset a wet or burning panel.
Sources
- EPA Section 608
- Energy Saver home heating systems
- Energy Saver air conditioning
- Ready.gov floods page