Johnson Controls York YHAU-C User Manual

Table 34: Troubleshooting the high temperature generator
Item Cause Countermeasure
3 Non-condensable gas stays in machine.
• See Purge procedure.
• Check the capacity of the vacuum pump.
• Check the purge unit for trouble.
• Purge air from the absorption chiller.
• If partial-load operation is continued for a long period, non-
condensable gas tends to stay in the absorber. In this case,
purge directly from the low-pressure side (absorber).
4
Heat exchange tube is dirty (Chilled water,
cooling water).
5 Solution is crystallized.
6 Corrosion inhibitor is worn.
7 Air leaks in absorption chiller.
Contact your local Johnson Controls Service Office.
Table 35: Chilled water overcooling or refrigeration overcooled
Item Cause Countermeasure
1
Chilled water flow rate lowers or changes
sharply.
Check if the chilled water flow rate changes suddenly (particularly in
the case of variable flow rate specification). If it changes suddenly,
apply a limit of the change rate to the chilled water flow control or
take another measure.
2
Cooling water temperature at inlet changes
sharply.
Check if the cooling water temperature at inlet changes sharply
(by checking start and stop of the fan). If the chilled water or the
refrigerant temperature is low, the chiller stops immediately but
does not perform the dilution operation. If left as it is, the solution
can crystallize in 4-5 hours. To prevent this, dilute the solution
according to the procedure shown in Manual refrigerant blowdown
and diluting method.
3 Load lowers sharply. Check if the load changes sharply.
4 Refrigerant is dirty (contains solution).
Check if the refrigerant refining operation has been performed
periodically. For the refrigerant refining method, see Refrigerant
refining method.
5 Heat exchange tube is dirty (chilled water).
6
Temperature controller or safety switch is
broken.
Contact your local Johnson Controls Service Office.
In the case of chilled water suspension, the absorption chiller does not perform diluting operation
but stops immediately. If the absorption chiller is left as it is, the solution in it can crystallize in 4-5
hours. To prevent this, dilute the solution according to “manual refrigerant blowing and diluting
method”.
Table 36: Chilled water suspension
Item Cause Countermeasure
1 Chilled water pump has a problem. Check the chilled water pump for a problem.
2 Chilled water flow rate is low.
Check to see if the chilled water flow rate is lower than the setpoint
of the water suspension switch. If it is low, check the flow controller,
check the strainer for clogging, and check the opening ratio of the
flow control valve.
3
Pressure transfer pipe of water suspension
switch is clogged.
4 Water suspension switch is broken.
Contact your local Johnson Controls Service Office.
If the chiller has a pump problem, it does not perform the diluting operation but stops immediately.
If left as it is, the solution in it can crystallize in 4-5 hours. To prevent this, contact your local Johnson
Controls Service Office immediately.
YHAU-C Single Effect Steam-Fired Absorption Chiller170

Johnson Controls York YHAU-C Specifications

General

Brand	Johnson Controls
Model	York YHAU-C
Category	Chiller
Language	English