The Advantages of P-Traps in a Condensate Line
- A P-trap on a condensation line prevents the air handler device in the air conditioning unit from affecting the condensation line. The air handler creates negative pressure, which can back up into the condensation lines through the drain line. Without a P-trap sealing off the condensation line from the drain line, the negative pressure would cause air to draw up and through the drain opening. The air pressure will not allow the condensation from draining, similar to clogging.
- The P-trap seals the condensation line from the drain line. The seal prevents air from backing up into the condensation line. Without the P-trap, the fan on the air-conditioning unit would draw air from outside and into the air conditioner through the condensation line. The P-trap prevents this air from being drawn into the system by the air-conditioner fan.
- Make sure the inlet side of the P-trap is positioned at a height of one pipe diameter above the condensation line outlet. A P-trap that is positioned too high will not allow the drain line to work properly, and the P-trap is useless.
- Inspect the air-conditioning unit and the P-trap each season. The P-trap has a tendency of drying out when the air conditioning is not in use for a long period of time. Colder areas of the country can also cause the moisture in the P-trap to freeze, damaging the P-trap. A P-trap must remain moist to get all the advantages from the device. A dry P-trap causes the seal around the inlet valve on the trap to crack and lose its integrity.