JOHNSON CONTROLS
115
SECTION 7 – MAINTENANCE
FORM 155.33-ICOM2.EN.GB
ISSUE DATE:12/4/2017
7
Dry Storage
Dry storage involves draining the water from the tubes.
It most often used when the unit is installed in an out-
door location.
Condition around the chiller-heater:
1. During the heating operation period, there is a
possibility that the cooling water may freeze.
2. The cooling tower is installed at the same level
(height) of the chiller-heater.
3. A lining pipe is used for the cooling water piping
system.
Do NOT leave any water in the absorber
and condenser tubes after draining them.
If you do, the heat transfer tubes will be
at high risk for corrosion.
Work Procedure
1. Drain all of the cooling water from the absorber
and the condenser.
2. Flow the clean water from the higher location
than the chiller-heater.
3. Feed the clean water continuously and clean the
tubes well.
4. Fill the absorber and the condenser with clean wa-
ter.
5. Circulate it with the cooling water pump for 30
minutes to 1 hour.
6. Drain all of the cooling water from the absorber
and the condenser.
7. Dry inside of each water chamber and heat trans-
fer tube well.
8. The unit is ready to operate in heating mode dur-
ing the heating season.
LD21006
Cooling
Tower
Open/close signal for three way valve
Start/stop signal for cooling tower fan
Strainer
Thermometer
Drain valve
Thermometer
Cooling water pump
Close
Water drained
P
T
T
Drain valve
Chiller-Heater
Close
Open
Open
FIGURE 40 -
DRY STORAGE DURING HEATING PERIOD
