Table of Contents
Advertisement
SECTION 8 – TROUBLESHOOTING
REFRIGERANT OVERCOOLED
ITEM
CAUSE
Chilled / hot water flow
1
rate drops or changes
suddenly.
Cooling water temperature
2
at inlet changes suddenly.
3
Load lowers quickly.
Refrigerant is dirty
4
(contains solution).
Heat exchange tube is
5
dirty (Chilled / hot water).
Temperature controller or
6
safety switch is broken.
If the chilled-heater / hot water flow stops, the chiller-
heater stops immediately without diluting the solution.
If the absorption chiller-heater is left as is, the solution
TABLE 28 - CHILLED / HOT WATER SUSPENSION
ITEM
CAUSE
Chilled / hot water pump
1
has a problem.
Chilled / hot water flow
2
rate is low.
Pressure transfer pipe of
3
water suspension switch
is clogged.
Water suspension switch
4
is broken.
If the chiller-heater has a pump problem, it stops im-
mediately without performing the dilution operation.
TABLE 29 - PUMPS OVERLOADED OR OVERHEATED
ITEM
1
Bearings of the pump are worn or clogged.
2
Pump is damaged by cavitation caused by low liquid level.
3
Thermal switch is not set properly.
4
Internal cycle control valve is not set properly.
5
Filter in the pump is clogged.
6
Solution is crystallized.
7
Circuit breaker has tripped.
116
See if the chilled / hot water flow rate changes quickly (particularly in the case
of variable flow rate specification). If the flow rate changes suddenly, apply a
limit of the change rate to the chilled / hot water flow control or remeasure.
See if the cooling water temperature at inlet changes quickly (by checking start
and stop of the fan). If the chiller-heater refrigerant temperature is low, the
chiller-heater stops immediately but does not perform the dilution operation.
If left as is, the solution may crystallize within 5 hours. To prevent this, dilute
the solution. See Manual Refrigerant Blowdown and Dilution Method on page
93.
See if the load changes unexpectedly.
See if the refrigerant refining operation has been performed periodically. For
the refrigerant refining method, see Refrigerant Refining Method on page 118.
Contact your local Johnson Controls Service Office.
in it may crystallize within 4-5 hours. To prevent this,
dilute the solution. See Manual Refrigerant Blowdown
and Dilution Method on page 93.
Check the chilled / hot water pump for a problem.
• Check to see if the chilled / hot water flow-rate is below the setpoint of the
water suspension switch. If it is low, check the flow controller.
• Check the strainer for clogging.
• Check the opening ratio of the flow control valve.
Contact your local Johnson Controls Service Office.
If left as is, the solution in it may crystallized in 4 - 5
hours. To prevent this, contact your local Johnson Con-
trols Service Office immediately.
CAUSE
FORM 155.35-ICOM2.EN.CE/GB (1018)
COUNTERMEASURE
COUNTERMEASURE
COUNTERMEASURE
Contact your local Johnson Controls Service
Office.
DATE: 10/30/2018
JOHNSON CONTROLS
Advertisement
Table of Contents
Troubleshooting
