Condensation Drain Lines and What You Need To Know
Condensation forms while you FAU operates. This condensation has to be removed, therefore a drainage system is designed into the FAU in two parts. The primary and the secondary condensation drain lines.
The primary condensation drain line is designed to drain into the household sewer system through a drain line connection to an active p-trap. The p-traps are similar to what we see used in a bathroom sink p-trap.
If the evaporator coil’s primary drain line becomes clogged or develop a leak, condensation should overflow or leak into the drain pan installed for this type of situation and then into the emergency drain line. The secondary emergency condensation drain line, drains to a conspicuous place outside the home. You find these terminated above a window or even a door. Water dripping from the secondary drain line is a warning that something is wrong with the primary condensation drain system. Call a service technician quickly.
Condensation Drain Problems
With primary condensation drain lines stem form plant pollen, fungus spores and other particulate matter entrained in the air stream passing over the wet evaporator coil. They are captured by the condensation draining off the coil and are carried into the drain system. There they produce algae, mildew, and fungus growths which can clog the primary drain system. The secondary drain lines are normally dry and clear, they are open to the atmosphere. Wasps are known to nest in these open drain lines, there by rendering them useless; always at the wrong time.
The larger diameter pipe of the household sewer system yields two results. It many times creates problems with condensation. Second, the maintenance and repair beyond the open connection to the p-trap is outside the scope of the air conditioning technician. Some older systems drain into an inactive p-trap. This can lead to the long term build up of sediment, dried algae, etc… in the trap and result in an overflow of the plumbing drain system. If the active p-trap also services a bath tub or bathroom sink, clogs can be caused by hair, soap scum or other material draining from the tub or sink. Clogs in the household sewer system require the services of a licensed plumber.
Condensation Drain Maintenance
Test both the primary and secondary drains with water. If a restriction is detected, clear the obstruction with compressed air. Blowing out a drain line will usually open a clogged drain line, but it cannot remove growing algae or other deposits from the pipe wall. Placing algicide tablets in the primary drain pan is a solution often used. While algicide is used to prevent algae buildup, algicide kills any existing algae. The dead algae may slough off the pipe wall and pass into the sewer system or drift down stream to a restriction and accumulate there resulting in a clogged drain.
Other Condensation Drain Information
Bathtub or bathroom sink p-traps. If the active p-trap in your system is the trap for a bath tub or bathroom sink, there is the possibility that material flushed from the condensation drain system may combine with bathroom debris already in the trap, to begin formation of a clog. Should one of these plumbing drains clog, condensation will fill the sink or tub and overflow without any warning such as water dripping form the emergency drain line. After any work on your condensation drain system, the drainage of the sink and tub should be checked. If either drains slowly or backs up, plumbing maintenance is needed.
The installation of a float switch in the emergency condensation drain pan and an Easy Klear clean out valve is another form of insurance that can used to help signal and remedy a problem. Should both the primary and secondary drain systems fail, the float switch functions to turn off the air conditioning system, stopping the production of condensation until the clog is cleared and the drain pan emptied. The Easy Klear helps improve drain line maintenance.
There can be no guarantee that your condensation drain system will remain clear. A condensation drain system can become clogged at anytime and should be monitored after it has been serviced, especially when algicide has been applied. Some older systems with accumulations of algae can become clogged anytime algae breaks loose from the pipe wall and drifts downstream to a restricted point. At a restriction, algae will accumulate and grow unit it blocks the drain pipe. These restrictions can grow into a fully clogged drain line in less than one month.
Should a problem occur with the p-trap or plumbing drain line it is recommended to call a licensed plumber. Blowing out a large diameter plumbing drain line is not an effective repair. The household sewer system, beginning at the open connection to the condensation system, is the domain of the licensed plumber.
Whenever the air handling unit of an air conditioning system is located in an attic or the upper stories of a building, the risk of water damage due to drain stoppage and condensation overflow is inherent and unavoidable. Proper design and installation coupled with timely and consistent maintenance can minimize the probability of an overflow, but cannot absolutely prevent it. Most warranties specifically exclude liability for water damage due to condensation overflow, and special, consequential or incidental damage caused by stoppage of a condensation drain system.
Homeowner’s insurance should include coverage for water damage resulting from condensation overflow or other water leaks. Be sure you confirm your coverage.