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CLCH-SVX03C-EN
Routine Maintenance
Type K Coils
1.
Remove all vent and drain plugs.
2. Allow the water to drain from the coil.
3. Remove the header covers.
4. If tubes are fouled, clean the tubes with a nylon or wire brush.
5. To ensure no water remains in the coil, do not replace the header covers until the coils are put
back into service.
Note:
When the coils are put back into service, use new gaskets. Trane recommends washers be
used under the bolt heads and bolts be evenly tightened to 50 ft-lbs torque.
Moisture Purge Cycle
By it’s very nature, any HVAC unit with a cooling coil serves as a dehumidifier, reducing the
surrounding air’s ability to hold water vapor as its temperature falls. This normally doesn’t present
a problem when the unit is running. However, when the fan stops, water vapor condenses on the
cold metal surfaces inside the air handler and remains there until the air warms sufficiently to re-
evaporate it. This damp, dark environment—though temporary—can encourage the growth of
mold, mildew, and other microbial contaminants.
Providing a moisture purge cycle 15 to 30 minutes after shutdown disperses the cold, humid air
inside the air-handling system more evenly throughout the building. This four-step cycle:
•
Closes the outdoor air dampers.
•
Turns off the cooling coil.
•
Opens any variable-air-volume terminals connected to the air handler.
•
Operates the supply fan for 10 to 15 minutes.
Air movement discourages water condensation and hastens re-evaporation of any condensate that
does happen to form. This simple preventative measure effectively combats microbial growth and
curbs moisture-related deterioration of air-handling components.
Internal Insulation
NOTICE:
Microbial Growth!
Wet interior unit insulation can become an amplification site for microbial growth (mold), which
may cause odors and damage to the equipment and building materials. If there is evidence of
microbial growth on the interior insulation, the insulation should be removed and replaced prior
to operating the system.
The process of cooling and dehumidification produces condensate that must be continuously
removed from the air-handling unit. The section of the unit from the entering air side of the cooling
coil to the leaving edge of the drain pan is considered to be the “wet” section of the unit. Other
potentially “wet” sections are immediately downstream of a humidifier and/or an outside air intake
section.
Internal insulation in areas of the unit that are normally considered to be “dry” must also be
periodically inspected to assure the insulation is clean and dry. Wet insulation in an area that is
normally considered to be “dry” can indicate an operational problem (refer to the
“Troubleshooting” section on page 94
for further information). The equipment should be
inspected a minimum of every six months or more frequently as operating experience dictates.