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Clean the fan-coil units main and auxiliary drain pans to ensure the
unit drains condensate properly.
Check the condensate drain pan and drain line to assure the conden-
sate drains properly at least every six months or as dictated by
operating experience.
If evidence of standing water or condensate overflow exists, immedi-
ately identify and remedy the cause. Refer to Table 40 on page 99 for
possible causes and solutions. If the drain pan contains microbial
growth, clean and remove it immediately.
Clean drain pans using the following procedure:
1. Disconnect all electrical power to the unit.
2. Don the appropriate personal protective equipment (PPE).
3. Remove all standing water.
4. Use a scraper or other tool to loosen any solid matter. Remove
solid matter with a vacuum device that utilizes high efficiency particu-
late arrestance (HEPA) filters with a minimum efficiency of 99.97% at
0.3 micron particle size.
5. Thoroughly clean the contaminated area(s) with a mild bleach and
water solution or an EPA-approved sanitizer specifically designed for
HVAC use. Carefully follow the sanitizer manufacturers instructions
regarding the use of the product.
6. Immediately rinse the drain pan thoroughly with fresh water to
prevent potential corrosion from the cleaning solution of the drain pan
and drain line components.
7. Allow the unit to dry thoroughly before putting the system back into
service.
8. Determine and correct the cause of the microbial contamination.
9. Be careful that the contaminated material does not contact other
areas of the unit or building. Properly dispose of all contaminated
materials and cleaning solution.
Note:
Standing water in drain pans can promote microbial growth
(mold) which may cause unpleasant odors and health-related indoor
air quality problems.
If microbial growth (mold) is found, remove it
immediately by cleaning and santizing the unit properly.
Inspecting and
Cleaning Drain
Pans