Your air conditioner can provide years of service without giving you problems. However, since there are several parts in an air conditioner, something will probably malfunction at some point, especially when your air conditioner is old. In some cases, your AC will shut itself down when there's a problem so no damage is done to the unit. Here are two safety mechanisms built into air conditioners that may cause your AC to stop functioning.
The Condensation Pan Float Switch
A float switch is a safety mechanism some air conditioning units have to prevent water damage to your HVAC and home. This switch is placed in the pan that collects condensation water.
Your AC dries out the air in your home as it cools it, and the AC might pull several gallons of moisture from your home daily. This water drips into a condensation pan, and then it drains out of the house or into a plumbing drain.
Clogs in the condensation pan line are fairly common, and when they occur, the pan stops draining and fills up with water. If it continues to fill up, water spills over the side and gets in the HVAC and can cause water damage to your floor.
To prevent this, your HVAC installer puts a float switch in the pan. Then, if the water level in the pain gets too high, the switch shuts down the air conditioner to alert you to the problem.
To get your AC working again, you'll have to clear the clog and drain the pan. You may need to hire an HVAC technician to do this. One thing to keep in mind is that a technician checks and cleans the line when you have an annual air conditioning tune-up, so keeping those appointments is a good way to avoid your AC shutting down to a condensation line clog.
The Safety Switch
When your air conditioner senses that it's overheating or struggling to operate, it will shut itself off to prevent damage. This might happen due to iced over coils, a clogged filter, a dirty blower assembly, a bad compressor, or even low refrigerant.
Sometimes, the AC runs for a short period and then shuts itself off only to start right back up and shut off again. Once this cycle has happened enough times, your AC shuts down and stays off until you or a technician fixes the problem.
If the cause is a clogged filter, you may fix the situation by putting in a new filter and allowing time for the ice to melt if any has formed. If the problem is with the refrigerant or air conditioning components, you'll need to call an air conditioning repair service to get your air conditioner back in shape so it runs without shutting down for protection.