3. After the refining process is complete, close the spindle in the valve (turn it to the right until it
stops).
4. 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:
The time required for refinement of the refrigerant depends on the current load
condition. Constantly check the liquid level in the refrigerant tank while the refrigerant is being
refined. If the refrigerant liquid level appears in the level gauge of the refrigerant tank, close
the valve immediately and completely.
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.
Note:
Perform the following procedure immediately after the power is restored.
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 (VB).
Note:
For the location of the refrigerant blow valve, see Figure 75.
3. Turn the spindle in the valve to the left with the 8 mm (0.3 in.) hexagon wrench. The refrigerant
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. As 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. Cavitation noise
comes out of the solution circulation.
153
Model YHAU-CGN/H-CXR(M)Double Effect Direct Fired Small Absorption Chiller-Heater