This air handler has the access panels removed during the installation process so the HVAC installation technician can make the final connections and adjustments. In clear view is the air handler blower compartment with the air handler blower. The air handler blower is comprised of an electric motor, a blower wheel, and a squirrel cage which holds it all together. Attached to the outside of the squirrel cage is a capacitor which is for the electric motor. All these air handler components combined blows air throughout the entire HVAC system including the evaporator coil.
As the air handler blower blows air throughout the HVAC system sometimes this air contains extra moisture. If the air conditioner condenser is running the evaporator coil condenses the moisture in the air and this moisture needs a place to drain. In front of the air handler and attached to the lower part of the evaporator coil is the air handler evaporator condensation drain pipe. The air handler evaporator coil condensation drain also has a trap installed in it. The trap visible in the picture is a running trap. Traps are necessary in any type of drain and they prevent (unless they are dry) positive outside pressure from pushing air into the air handling system. Condensation drain pipes in air conditioner air handlers commonly plug up with debris and forms of algae and need to be purged from time to time.
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