Johnson Controls York MaxE YK Series, Manual

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FORM 160.75-O1 (309)
35
JOHNSON CONTROLS
leaK testing
The unit should be leak tested monthly. 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 condition.
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 condenser
tubes require cleaning. Refer to the Maintenance
section of this manual for condenser tube cleaning
instructions.
2. The evaporator tubes under normal circumstances
will not require cleaning. If the temperature differ-
ence 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.
3. Heat recovery condenser tubes should be evaluated
similiar to evaporator tubes when the heating circuit
is a treated, closed loop. Fouling could be detected as
ability to meet heat load requirements decreases.
oil return sYstem
1. Change the dehydrator in the oil return system semi-
annually 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 particles
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 settings
are changed without Johnson Controls approval, the
warranty will be jeopardized.
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