SECTION 7 – MAINTENANCE
FORM 155.32-ICOM2.EN.UL
ISSUE DATE:1/10/2018
138
JOHNSON CONTROLS
DECRYSTALLIZATION
1. Stop the 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 Panel.
4. Press the Forced Dilution
ON
button.
5. Remove the cap of the refrigerant manual blow- down valve.
6. Turn the spindle in the valve to the left with the 8 mm hexagon wrench.
7. Watch the liquid level of the refrigerant tank.
8. Immediately after the refrigerant liquid level appears in the level gauge of the refrig-
erant tank, close the refrigerant manual blow-down valve (turn it to the right until it
stops).
9. Press the Refrigerant Pump
Stop
button. The refrigerant 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 solution pump starts.
13. Press the Control Valve Mode
Manual
button.
14. Set the Valve Position Setting to 30 - 40%. For detailed information on how to change
the setting, see
Purge Valve Operation on page 133
.
15. Observe the liquid level in the absorber.
16. When the liquid level in the absorber drops, press the Forced Dilution
OFF
button.
17. Repeat steps 12 through 16 three - four times. If the liquid level in the absorber does
not go down, the crystals have melted.
18. Let the solution pump operate independently for about 30 minutes. Constantly ob-
serve the liquid level in the absorber while the solution pump operates.
19. After about 30 minutes, stop the solution pump.
20. Press the Refrigerant Pump
Auto
button.
21. Return the valve cap. There is an O-ring between the cap and valve. When fitting the
cap, make sure that the O-ring is set normally.
NOTE: Since the electrical wiring of the solution pump is disconnected, only the refrig-
erant pump starts.
NOTE: For the location of the refrigerant manual blow valve, see Figure 36 on page 133.
NOTE: The refrigerant in the refrigerant tank diverts into the absorber.
