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JOHNSON CONTROLS
124
FORM 155.32-ICOM1.EN.GB
ISSUE DATE: 10/13/2017
SECTION 6 – OPERATION
OPERATION MODE CHANGEOVER
Changeover to Cooling Mode
1. Press and hold the Operation Mode
Cooling
but-
ton on the Setting screen for 15 seconds. See
2. Press the Cool or Heat Simultaneous
OFF
button
3. Press the RHW only operation
OFF
button (if ap-
plicable) on the Setting screen.
4. Set each cooling or heating changeover valve to
for in-
formation.
5.
Verify the cooling water piping system is filled
with water.
6. Verify that the tapped air is vented.
7. Open (or close) each valve in the cooling water
piping system to ensure the cooling water circula-
tion in the system.
8. Manually operate the cooling water pump and
cooling tower fan.
9. Verify these can be operated and the cooling water
is circulated.
Do NOT operate the cooling water pump
without operating the chilled/hot water
pump to prevent the freezing of chilled/
hot water.
10. While the chiller-heater is stopping, purge the
purging tank, See
Condensable Gas from the Purge Tank on page
.
11. While the chiller-heater is stopping, purge the
absorber, See
Condensable Gas Directly from Absorber on page
12. Operate the chiller-heater.
13. Purge the absorber again. See
Purge Non-Condensable Gas Directly from Ab-
.
14. Press the Purge Mode
Auto
button on the Setting
Automatic Method to Purge Non-con-
densable Gas from the Purge Tank on page 135
Changeover to Heating Mode
1. Select the appropriate method to treat the cooling
water in the absorber and condenser tubes during
the heating operation period. See
of the Cooling Water During Heating Operation
.
If the operation mode (Cooling or Heat-
ing) is changed periodically, clean each
heat transfer tube with a nylon brush
during this step.
2. Press and hold the Operation Mode
Heating
but-
ton on the Setting screen for 15 seconds. See
3. Press the Cool or Heat Simultaneous
OFF
but-
ton on the Setting screen. See
4. Press the RHW only operation
OFF
button (if ap-
plicable) on the Setting screen.
5. Set each cooling or heating changeover valve to
Heating mode. See
6. While the chiller-heater is stopping, purge the
purge tank. Use the procedure shown in
Method to Purge Non-Condensable Gas from the
.
7. Close all of the manual valves in the purge line
(V10, V11, V12, V13, V14, V15, and V16).
8. Press the Purge Mode
Auto
button on the Setting
screen.
Use Simultaneous Residential Hot Water
Supply Mode (Option)
In this mode, residential hot water is supplied through
the auxiliary heat exchanger (option) while chilled wa-
ter or hot water is supplied through the evaporator.
1. Check that the correct Operation Mode button
(
Cooling
or
Heating
) is pressed on the Setting
screen. See
.
If you need to change the operation mode,
remember to press and hold the button for
15 seconds.