3.Using an inclined manometer, determine the pressure drop across a dry indoor coil. Since the moisture on an indoor coil may vary greatly, measuring the pressure drop across a wet coil under field conditions would be inaccurate. To ensure a dry coil, the compressors should be
4.Knowing the pressure drop across a dry coil, the actual airflow through the unit can be determined from the curve in Figure 11.
WARNING: Failure to properly adjust the total system air quan- tity can result in poor system performance.
After readings have been obtained, remove the tubes and seal the drilled holes in the side panels. 8mm (5
16in.) dot plugs (P/N
NOTE:
TAKING ANY TEST MEASUREMENTS TO ENSURE
A DRY INDOOR COIL.
SECURE OWNER'S APPROVAL: When the system is functioning properly, secure the owner's approval. Show him the location of all disconnect switches and the thermostat. Teach him how to start and stop the unit and how to adjust temperature settings within the limitations of the system.
MAINTENANCE
NORMAL MAINTENANCE
CAUTION: Prior to any of the following maintenance proce- dures, shut off all power to the unit to prevent per- sonal injury.
FILTERS - Inspect once a month. Replace disposable or clean permanent type as necessary. DO NOT replace permanent type with disposable.
MOTORS - Indoor fan and outdoor fan motors are permanently lubricated and require no maintenance.
OUTDOOR COIL - Dirt should not be allowed to accumulate on the outdoor coil surface or other parts in the air circuit. Cleaning should be as often as necessary to keep coil clean. Use a brush, vacuum cleaner attachment, or other suitable means. If water is used to clean coil, be sure power to the unit is shut off prior to cleaning.
NOTE: Exercise care when cleaning the coil so that the coil fins are not damaged.
Do not permit the outdoor air discharge to be ob- structed by overhanging structures of shrubs.
14 | Unitary Products Group |
