2. Under normal circumstances, the evaporator tubes do not require cleaning. If the
temperature 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 waterbox requiring gasket replacement or refrigerant
may have leaked from the chiller.
3. Evaluate heat recovery condenser tubes in a similar manner to evaporator tubes when the
heating circuit is a treated, closed loop. Fouling could be detected as the 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, check the nozzle of the eductor for any foreign particles
that may be obstructing the jet.
Electrical controls
1. Inspect all electrical controls for obvious malfunctions.
2.
Do not
change the factory settings of controls (operation and safety). If the settings are
changed without Johnson Controls approval, the warranty will be jeopardized.
43
Model YK Style G R-134a or R-513A
