6. Close all of the manual valves in the purge line (VC and V15).
7. 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 water 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 Figure 64.
Note:
If you need to change the operation mode, remember to press and hold the button
for 15 seconds.
2. Press the Simultaneous
ON
button on the setting screen.
3. Press the RHW only operation
OFF
button on the setting screen.
4. Set each cooling or heating changeover valve and manual valve to the wanted operation mode
(“Simultaneous cooling and residential hot water supply” mode or “Simultaneous heating and
residential hot water supply” mode).
Changeover to simultaneous hot water sole supply mode
(option)
Note:
This changeover process is suitable for high temperature hot water design chiller-
heaters, where the unit changes from cooling to heating.
In this mode, residential hot water is supplied through the auxiliary heat exchanger (option). No
chilled/hot water is supplied through the evaporator.
1. Choose how to treat the cooling water in the absorber and condenser tubes during the
residential hot water supply operation period. See
Storage method of the cooling water during
for more information and instructions.
2. Choose how to treat the chilled/hot water in the evaporator tubes during the residential
hot water supply operation period. See
Storage method of the cooling water during heating
for more information and instructions.
3. Verify that the following two manual valves are open:
a. On the weak solution line from the low-temperature heat exchanger to the solution flow
control float valve in the high-temperature generator (V3).
b. On the strong solution line from the high-temperature heat exchanger to the solution
spray pump (V2).
4. Press and hold the forced dilution
ON
button on the setting screen for 10 seconds. See Figure
5. The solution pump and refrigerant pump starts independently.
Note:
The chilled/hot water pump must be operating during forced dilution to prevent
freezing of the chilled/hot water.
139
Model YHAU-CGN/H-CXR(M)Double Effect Direct Fired Small Absorption Chiller-Heater
