JOHNSON CONTROLS
143
SECTION 7 – MAINTENANCE
FORM 155.32-ICOM1.EN.GB
ISSUE DATE: 10/13/2017
7
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 crystallization
is detected. If the crystals cannot be melted by the fol-
lowing procedure, notify your local Johnson Controls
Service Center immediately.
Indications of Crystallization
•
The refrigerating capacity goes down. The liq-
uid level in the absorber drops. Cavitation noise
comes out the solution circulation or the solution
spray pump.
•
One of the following buttons is lit and the solution
pump trips:
•
Sol. Circu P. Abnormal
•
Sol. Spray Pump Abnormal
•
The solution level can be seen through the level
gauges on the high temperature generator.
•
The liquid level in the absorber is low and the so-
lution level can be seen through the high tempera-
ture generator level gauges (G104) white.
•
The liquid level in the absorber falls and the tem-
perature of the solution returning from the genera-
tor is drops.
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 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.
For the location of the refrigerant manual
blow valve, see Figure 51 on page 131
and Figure 52 on page 132 .
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.
