There are two storage methods available for the chiller-heater during off-season (winter) or plant
suspension: the wet storage method and the dry storage method.
Note:
The wet storage method is available where heat source water and hot water does not
freeze only.
Each storage method has its own characteristics. Select the method to use based on the plant’s
features and the storage period. The details are as follows:
Wet storage method
The wet storage method can be used when there is no concern about water freezing in winter.
Store the machine in a place where the ambient temperature remains higher than 32°F (0°C).
If it is likely that the temperature can drop below that, provide a heater for the machine. If a heater
is not possible, contact your local Johnson Controls service center for further information. For
details on the wet storage method, see
The wet storage procedure is as follows if either chilled/hot line or the cooling water line is an open
system:
1. Completely drain the water from the systems if it has deteriorated in quality.
2. Clean the water systems by passing clear water through them from a position higher than the
chiller-heater.
3. Fill the water systems with clear water.
4. Circulate the clear water through the water pump for 30 minutes to one hour to clean it.
5. Drain the water.
6. Completely fill the water systems with clear water again.
7. Store the machine.
Dry storage method
The dry storage method must be used if the chilled/hot water system or the cooling water system
can freeze in the winter or, if the water system has a lining tube.
Note:
Do not simply drain the chilled/hot, and the cooling water and store the machine. This
significantly increases the possibility of corrosion of the heat transfer tube and rust.
The dry storage procedure is as follows if either the chilled/hot line or the cooling water line is an
open system:
1. Completely drain the water.
2. Clean the water systems by passing clear water through them from a position higher than the
chiller-heater.
3. Fill the water systems with clear water.
4. Circulate the clear water through the water pump for 30 minutes to one hour to clean it.
5. Drain the water from each waterbox.
6. Dry the interior of each waterbox and the heat transfer tube.
Model YHAU-CGN/H-CXR(M)Double Effect Direct Fired Small Absorption Chiller-Heater
164
