FORM 155.32-ICOM2.EN.UL
SECTION 7 – MAINTENANCE
ISSUE DATE:1/10/2018
JOHNSON CONTROLS
137
MANUAL REFRIGERANT BLOW DOWN AND DILUTING METHOD
When the chiller-heater stops suddenly due to a power failure, the solution can become
crystallized. If this happens, dilute the solution manually according to the following
procedure.
1. Press the Forced Dilution
ON
button The solution pump and the refrigerant pump
start.
2. Remove the cap of the refrigerant manual blow valve.
3. Turn the spindle in the valve to the left with the 8 mm hexagon wrench. The refriger-
ant in the refrigerant tank is diverted into the absorber.
4. Watch the liquid level of the refrigerant tank. Immediately after the refrigerant liquid
level appears in the level gauge of the refrigerant tank, close the valve (turn it to the
right until it stops).
5. Press the Refrigerant Pump
Stop
button. The refrigerant pump stops.
6. Let the solution pump operate independently for 30 minutes.
7. Press the Forced Dilution
OFF
button to stop the solution pump.
8. Press the Refrigerant Pump
Auto
button.
9. 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.
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 difficult to melt the crystals
as time passes, perform the following operation immediately when crystallization is
detected. If the crystals cannot be melted by the following procedure, notify your local
Johnson Controls Service Center immediately.
Indications of Crystallization
• The refrigerating capacity goes down. The liquid level in the absorber drops. Cavita-
tion 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 gen-
erator.
• The liquid level in the absorber is low and the solution level can be seen through the
high temperature generator level gauges (G104) white.
• The liquid level in the absorber falls and the temperature of the solution returning from
the generator decreases.
NOTE: Perform the following procedure immediately after the power is restored.
NOTE: For the location of the refrigerant manual blow valve, see Figure 59 on page 124.
