COIL MAINTENANCE
1. Coils must be clean to obtain maximum performance. Check once a year under normal operating
conditions and, if dirty, brush or vacuum clean. Soiled fins reduce the capacity of the coil, demand more
energy from the fan, and create an environment for odor and bacteria to grow and spread through the
conditioned zone. High pressure water (400 psi or less) may be used to clean coils with fin thickness over
0.006 inches thick.
TEST THE SPRAY PRESSURE
over a small corner of the coil to determine if the fins
will withstand the spray pressure.
For coils with fragile fins or high fin density, foaming chemical sprays and washes are available. Many coil
cleaners contain harsh chemicals, so they must be used with caution by qualified personnel only. Care
must be taken not to damage the coils, including fins, while cleaning.
CAUTION: Fin edges are sharp.
2. Drain pans in any air conditioning unit will have some moisture in them, therefore, algae and other
organisms will grow due to airborne spores and bacteria. Periodic cleaning is necessary to prevent this
build-up from plugging the drain and causing the drain pan to overflow. Inspect twice a year to avoid the
possibility of overflow. Also, drain pans should be kept clean to prevent the spread of disease. Cleaning
should be performed by qualified personnel.
WINTERIZING COILS
Coil freeze-up can be caused by such things as air stratification and failure of outdoor air dampers and/or
preheat coils. Routine draining of water cooling coils for winter shutdown cannot be depended upon as
insurance against freeze-up. Severe coil damage may result. It is recommended that all coils be drained as
thoroughly as possible and then treated in the following manner.
Fill each coil independently with an antifreeze solution using a small circulating pump and again thoroughly
drain. Check freezing point of antifreeze before proceeding to next coil. Due to a small amount of water always
remaining in each coil, there will be diluting effect. The small amount of antifreeze solution remaining in the coil
must always be concentrated enough to prevent freeze-up.
NOTE:
Carefully read instructions for mixing antifreeze solution used. Some products will have a higher freezing
point in their natural state than when mixed with water.
Maintenance Instructions:
Optional Cooling Coils
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