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JOHNSON CONTROLS
96
FORM 155.35-ICOM2.EN.CE/GB (1018)
DATE: 10/30/2018
SECTION 7 – MAINTENANCE
TABLE 20
- MAINTENANCE AND INSPECTION
TASK
CONTENTS
FREQUENCY
SCOPE
Measurement of insulation
resistance of electric
devices
Measure the insulation resistance of the main circuit and
motors (solution pump, refrigerant pump) mainly to check
for lowering of insulation. When measuring the insulation
resistance, be sure to disconnect the wires of the
temperature controller, and other pertinent connections
that could effect measuring the insulation.
Yearly
S
Check terminal connections Check each terminal in the control panel for looseness.
S
Check operation of control
panel
Check the operation of the control panel to prevent
troubles caused by malfunction of the control panel.
S
Check performance of purge
unit
See
Performance Check Method of Vacuum Pump on
. Check the performance of the purge unit
periodically.
Monthly
S
Check leakage through
purge solenoid valves
By measuring vacuum down speed, check for leakage
through purge solenoid valves.
Yearly
S
Overhaul check of purge
solenoid valves
Perform overhaul of purge solenoid valves periodically.
S
Check airtightness
Measure the amount of non-condensable gas discharged
from the vacuum pump.
Every 2-3 months
S
Check continuity of
protective bonding circuit
Check continuity of protective bonding circuit.
Yearly
S
Analysis of quality of chilled
/ hot water and cooling
water
Reliable water treatment companies are available in most
larger cities to supply a water treating process which will
greatly reduce the corrosive and scale forming properties
of almost any type of water. Be sure to request the first
analysis within one month after the test operation is
started.
Every 2-3 months
C
Check amount of solution
and refrigerant
The solution is not consumed, but the refrigerant is
discharged in small amounts each time purging is
performed. If the amount of the refrigerant drops too
low, the condensation preventive function does not work
normally. Check the amount of the refrigerant at least
once every year.
Yearly
(during operation
at 100%)
S
Disassembly inspection and
cleaning of solution pump
and refrigerant pump
Sleeve bearings are used for the solution pump and
refrigerant pump. These bearings are normally lubricated
with a solution of lithium bromide and refrigerant. Since
excessive wear can cause a pump problem, the pumps
will need to be disassembled and inspected. This is also a
good time to clean the internal strainer.
2-3 years or
8,000 hrs
S
Disassembly, inspection,
and cleaning of vacuum
pump
Disassemble, inspect, and clean the vacuum pump to
maintain its capacity.
4 years or
20,000 hrs
S
Replacement of gaskets of
airtight parts
Replace the gaskets of the airtight parts to maintain the
airtightness of the absorption chiller-heater.
4 years or
24,000 hrs
S
Inspection of chilled / hot
water box and replacement
of packing
Open the waterbox cover and check the inside paint for
damage. Check the inside of the tubes for scales.
Every 2 years
S
Inspection of cooling
waterbox and replacement
of gasket
Yearly
S
C = Customer, S = Johnson Controls Service