HVAC (Heating, Ventilation, Air Conditioning)

Friday, September 18, 2020

Condensate drain line termination with Fan Coil Unit in the ceiling space/attic

 In inspecting buildings I often see how incorrect terminations of condensate drain lines, especially those that are coming from out-of-sight ceiling or attic-mounted forced air units/air handlers, causes a lot of problems (moisture in the walls, ceilings; mold).  The primary condensate line must connect with the drain line before a P-trap.  There should always be a secondary drain pan under the fan coil unit/air handling unit.  The drain line from the spill pan should terminate at a place where any water coming from there is in plain view and necessary action can be taken when that is the case.

In the photos below, the condensate drain line is connected to the sink drain and the secondary drain is terminated over the bathtub.