drain line

How the Condensate Drain Tube Functions

condensate drain tube may play an important role in proper function of both your air-conditioning and heating systems. As a vital part of the cooling process, the evaporator coil in the central AC condenses water vapor into many gallons of condensate every day. Also, if your home utilizes a high-efficiency gas furnace, the secondary heat exchanger in this unit extracts extra heat from water vapor present in the furnace exhaust, producing condensate water that must be drained away.

Potential Condensate Drain Tube Issues

Air Conditioner

Condensate water generated by the AC evaporator coil drips down into a pan situated beneath the indoor air handler. Collected water then flows through a condensate drain tube into a connection with the household plumbing system.

Clogs originating in the drip pan — a common location for algae or mold growth — may block free flow through the condensate drain tube. A clogged drip pan rapidly overflows and continues to do so every time the system cycles on. Because the pan is located beneath the air handler, leakage is often not initially obvious to occupants. Significant water damage may occur before the problem is noticed.

High-Efficiency Furnace

As the secondary heat exchanger produces water, the liquid accumulates in a collection box, then flows by gravity through a sloped condensate drain tube and is discharged outside the house. A drain trap integrated into this system permits free condensate flow while preventing hazardous combustion fumes from leaking out of the furnace. 

A sensor detects blockage in the furnace condensate drain tube and automatically shuts down the furnace as a safety precaution. Locating and clearing the clog, including checking and cleaning the drain trap, are required in order to restart the furnace and restore normal heating.

Prevention

Annual preventative maintenance by a qualified HVAC service technician includes inspection and cleaning of the AC condensate drain tube as well as the furnace condensate drain system. This helps prevent condensate drain clogs before they interrupt normal cooling or heating operation.

For qualified service to prevent condensate drain tube issues — or promptly repair any that may occur — contact the professionals at Air Assurance.