York YHAU-CE-JE Series, Установка, эксплуатация и обслуживание, Страница: 98 / 136

JOHNSON CONTROLS
98
FORM 155.33-ICOM2.EN.GB
ISSUE DATE: 12/4/2017
SECTION 7 – MAINTENANCE
DECRYSTALLIZATION METHOD
Even if the solution in the absorption chiller-heater is
crystallized during operation, it can be melted if the
crystallization is not severe. Since it becomes more dif-
ficult to melt the crystals as time passes, perform the
following operation immediately when you see crystal-
lization. If the crystals cannot be melted using the fol-
lowing procedure, notify your local Johnson Controls
Service Center immediately.
Indications of Crystallization
• The refrigerating capacity goes down, the liquid
level in the absorber drops, and cavitation noise
comes out of the solution pump.
• The Solution Circulation P Abnormal or the
Solution Spray Pump Abnormal buttons on the
Failure screen light and the solution pump trips.
• The liquid level in the absorber is low. The solu-
tion level seen through the high temperature gen-
erator level gauge (LG3) is white.
• The liquid level in the absorber drops and the tem-
perature of the solution returning from the high
temperature generator goes down.
Decrystallization
1. Stop the absorption chiller-heater. If the solution
pump tripped, reset the thermal relay.
2. Disconnect the electrical wiring of the solution
pump.
3. Navigate to the Setting screen on the Control Pan-
el.
4. Press the Forced Dilution ON button.
Since the electrical wiring of the solution
pump is disconnected, only the refrigerant
pump starts.
5. Remove the cap of the refrigerant manual blow-
down valve V2.
For the location of the refrigerant manual
blow valve, see Figure 35 on page 95 .
6. Turn the spindle in the valve to the left with the 8
mm hexagon wrench.
The refrigerant in the refrigerant tank
diverts into the absorber.
7. Watch the liquid level of the refrigerant tank.
8. Immediately after the refrigerant liquid level ap-
pears in the level gauge of the refrigerant tank,
close the refrigerant manual blow-down valve
(turn it to the right until it stops).
9. Press the Refrigerant Pump Stop button. The re-
frigerant pump stops.
10. Press the Forced Dilution OFF button.
11. Re-connect the electrical wiring of the solution
pump.
12. Press the Forced Dilution ON button. The solu-
tion pump starts
13. Navigate to the Main screen on the Control Panel
14. Set the temperature controller (TIC) to manual
mode for the:
a. waste exhaust gas
b. waste hot water
15. Adjust both to 30-40%
16. Watch the liquid level in the absorber while you
perform the adjustments
17. When the liquid level in the absorber drops, set
the temperature controllers to 0% for the :
a. waste exhaust gas
b. waste hot water
18. Navigate to the Control Panel Setting screen.
19. Press the Forced Dilution
OFF
button.
20. Repeat steps 12 - 19 three to four times.
21. If the liquid level in the absorber does not drop,
the crystals have melted.
22. Press the Forced Dilution
ON
button. The solu-
tion pump operates independently. Let it run for
approximately 30 minutes.