Cleaning Procedure; Condensate Drain Pan, Trap And Line Cleaning; Tools, Equipment And Materials; Schedule And Conditions - York AHU Operation And Maintenance

FORM 102.20-OM2
ISSUE DATE: 6/01/2015

Cleaning Procedure

1. Clean dehumidification coils annually or when air
pressure drop exceeds 125% of design.
2. Cover electrical components such as fan mo-
tors, damper motors, compressors, thermostats,
etc. with plastic. Care should be taken on interior
coil cleaning. Remove filters; cover fan bear-
ings and any insulation to keep these items free
of water damage. Condensate drain piping should
be screened to allow coil-cleaning water to flow
freely. Screening keeps traps and drain lines from
clogging with debris washed from the coils.
3. Prior to any application of wet cleaning materials,
use a wide soft bristle paint brush to dust off any
heavy dust, leaves, bugs or other foreign matter
that may be on the coil fin surface.
4. Safety glasses should be worn when cleaning
coils.
5. When possible, remove dirt lodged in the depth of
the coil by using clean oil-free air under pressure.
Caution should be taken not to use extreme high-
pressure air as this may cause fin surface damage.
Direct the air straight at the openings between
the fins and never at an angle, which may bend
the fins against one another. Always apply the air
from the air leaving side of the coil.
6. On heavily soiled coils, use a safe commercial
grade coil cleaner.
7. Follow the safety and mixing instructions as noted
on or with the cleaning agent.
8. Spray the cleaning agent on both sides of the coil
to be cleaned. Allow the cleaning agent to remain
in contact with the dirty surface for about 5 min-
utes or as recommended by the agent instructions.
Then flush the coil with clean water from a hose
(with spray nozzle or from pressure washer).
Flush from the air leaving side of the coil. Cau-
tion should be taken, as extreme water pressure
may result in fin surface damage. Direct the water
straight at the openings between the fins and never
at an angle, which may bend the fins against one
another. This process will wash away surface dirt
on the air entering side of the coil, and prevent it
from loading within the depth of the coil.
JOHNSON CONTROLS
9. Most cleaners are concentrated detergents and can
be diluted with up to 10 parts water. Dilute as per
cleaning agent instructions and coil condition. Re-
spray both sides of the coil with cleaner. Allow to
stand five minutes and flush as described previ-
ously. Finish flushing from both sides of the coil.
10. Follow the cleaning agent instructions. Agent
should meet environmental and OSHA standards.
11. Some extreme oil and dirt conditions may require
steam cleaning. Most steam equipment can be ad-
justed to provide a mixture of water and steam at a
moderate pressure. Steam alone without the pres-
ence of water does not work well with most clean-
ing agents. Cleaning the coils with steam should
be done as described previously.
12. Comb out any bent or flattened areas of the fin
surface.
13. Restore the equipment to its operational state.
CONDENSATE DRAIN PAN, TRAP AND LINE
CLEANING

Tools, Equipment and Materials

• Toilet bowl brush or similar utility cleaning brush
• Cleaning agent (safe, commercial, disinfecting)
• Rags and trash bags
• Garden hose with spray nozzle or power washer
• Scraper
• Screening
• Wet vacuum

Schedule and Conditions

1. Clean condensate drain pan, trap, drain line and
adjacent wetted surfaces at least annually or as
often as required to retard growth of microbial
substances.
2. Test Drain Pans - To minimize conditions of wa-
ter stagnation that may result in microbial growth,
field test drain pans under normal operating con-
ditions to ensure proper drainage.
3. Exception - Field testing drain pans is not re-
quired if units with factory-installed drain pans
have been certified (attested in writing) by the
manufacturer for proper drainage when installed
as recommended.
SECTION 3 - MAINTENANCE
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