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2.
Check and optional integral chiller and/or
process pump discharge pressures. Investigate
further if the pressure starts to stray away from
the normal operating pressure.
3.
Check the suction and discharge refrigerant
pressure at the compressor.
4.
Check each refrigerant sight glass for air bubbles
or moisture indication. Bubbles in the refrigerant
indicate either low refrigerant charge or
excessive pressure drop in the liquid line. If the
sight glass indicates that there is a refrigeration
problem, have the unit serviced as soon as
possible.
5.
Check the compressor oil level in the sight glass.
View the oil level through the sight glass while
the compressor is running. The level will vary as
the compressor loads and unloads.
Once a Month
Repeat items 1 through 5 and continue with the
following.
6.
Check the Y strainer between the return
connection and the evaporator inlet. Open the
blow-down valve attached to the strainer to
flush the screen free of debris.
7.
Check the flow sensor tip visually for signs of
build-up and clean with a soft cloth. Is there is
some suborn calcium build-up that is not easily
removed with a soft cloth use household vinegar
as a cleaning agent to remove the deposit.
8.
Shut off the power disconnect. Check the
condition of electrical connections at all controls.
Check for loose or frayed wires.
9.
Check the main power supply to ensure it is
acceptable, connected properly, and the unit has
a proper ground (see Installation section of this
manual for details).
10.
Check the amp draws to each leg of the
compressor(s) to confirm that it is drawing the
proper current.
11.
Check the system superheat and sub-cooling.
Normal superheat is approximately 10°F;
however, it may be high but not more than 15°F.
Normal sub-cooling ranges from 10°F to 20°F.
Once Every 6 Months
Repeat items 1 through 11 and continue with the
following.
12.
Check for visible mechanical damage to the
compressor.
13.
Check for excessive vibration from other rotating
equipment.
14.
Check for signs of hot spot/discoloration on
power cables.
15.
Check all communication cables are secure and
tight.
16.
Check all electrical modules are secure.
17.
Check system refrigerant charge and verify the
system is still full charged.
18.
Check the operation of the compressor
crankcase heater. Energize the heater while the
compressor is off. Taking an amp reading of the
heater leads is the best way to determine the
correct operation. Another way is to feel if there
is localized heat around the crankcase heater
when the heater is on.
Once a Year
Repeat items 1 through 18 and continue with the
following.
19.
Check the condition of the chilled water for
algae and particulate fouling. Back flush the
evaporator with water or another suitable
cleaning agent. The frequency at which this task
is required depends on specific site conditions.