York YD A, Operating & Maintenance, Page: 50 / 52

JOHNSON CONTROLS
50
FORM 160.69-O2
ISSUE DATE: 9/30/2020
SECTION 7 – PREVENTIVE MAINTENANCE
• Add 1.5 cubic inches of Texaco Premium RB
grease every 1800 hours of operation of the mo-
tor. Do not expect to see grease exiting the grease
relief port during these re-lubrications.
Westinghouse Motor Lubrication:
• Re-greasing should occur at 1000 operating hour
intervals.
• Westinghouse recommends using Westinghouse
Grease No. 53701.
• Motors with shaft diameters less than 2 3/8 inch
require 1 oz of grease per bearing while motors
with shaft diameters between 2 3/8 and 3 inches
require 1.5 oz.
Recommended greases for standard applications:
OPERATING AMBIENT TEMP. -30ºC TO 50ºC
Chevron SRI (Chevron)
Exxon Unirex #2 (Exxon Corp.)
Exxon Polyrex (Exxon Corp.)
Shell Dolum R (Shell Oil Co.)
Mixing different greases is not recom -
mended.
Additional information on motor lubrica-
tion and other service issues can be found
in the A-C Motors Instruction Manual.
LEAK TESTING
The unit should be leak tested quarterly. Any leaks
found must be repaired immediately.
EVAPORATOR AND CONDENSER
The major portion of maintenance on the condenser
and evaporator will deal with the maintaining the water
side of the condenser and evaporator in a clean condi-
tion.
The use of untreated water in cooling towers, closed
water systems, etc. frequently results in one or more of
the following:
1. Scale Formation.
2. Corrosion or Rusting.
3. Slime and Algae Formation.
It is therefore to the benefit of the user to provide for
proper water treatment to provide for a longer and
more economical life of the equipment. The following
recommendation should be followed in determining
the condition of the water side of the condenser and
evaporator tubes.
1. The condenser tubes should be cleaned annually
or earlier if conditions warrant. If the temperature
difference between the water off the condenser
and the condenser liquid temperature is more than
4°F (2°C) greater than the difference recorded on
a new unit, it is a good indication that the con-
denser tubes require cleaning. Refer to the Main-
tenance section of this manual for condenser tube
cleaning instructions.
2. The evaporator tubes under normal circumstances
will not require cleaning. If however the temper-
ature difference between the refrigerant and the
chilled water increases slowly over the operating
season, it is an indication that the evaporator tubes
may be fouling or that there may be a water bypass
in the water box requiring gasket replacement or
refrigerant may have leaked from the chiller.
OIL RETURN SYSTEM
1. Change the dehydrator in the oil return system
semiannually or earlier if the oil return system
fails to operate.
2. When the dehydrator is changed, the nozzle of the
eductor should be checked for any foreign par-
ticles that may be obstructing the jet.
ELECTRICAL CONTROLS
1. All electrical controls should be inspected for ob-
vious malfunctions.
2. It is important that the factory settings of controls
(operation and safety) not be changed. If the set-
tings are changed without YORK’s approval, the
warranty will be jeopardized.