FORM 155.32-ICOM2.EN.UL
SECTION 7 – MAINTENANCE
ISSUE DATE:1/10/2018
JOHNSON CONTROLS
153
STORAGE METHOD OF THE COOLING WATER DURING HEATING
OPERATION PERIOD
Do NOT operate the cooling water pump during operation in heating mode, simultaneous
heating and residential hot water supply mode, and residential hot water only (sole) supply
mode.
Treat the cooling water in the absorber and condenser tubes during the heating operation
using one of the following two methods.
Wet Storage
This method of storage leaves water in the tubes. It is applicable to indoor installations.
Condition around the chiller-heater:
1. During the heating operation period, there is no concern about the cooling water freez-
ing. (In case there is concern of freezing, apply insulation material to the cooling water
piping.)
2. The cooling tower is installed at the high level (height) of the chiller-heater to prevent
water from flowing into the cooling tower.
3. Lining pipe is not used for the cooling water piping system. If you use the lining pipe,
use a heat -resistant lining pipe.
CAUTION: To avoid risk of corrosion of the heat transfer tubes, do NOT leave any poor
quality cooling water in the absorber and condenser tubes.
DANGER: Cooling water temperature can rise up to approximately
176°F (80°C).
due
to the residual heat during heating operation. Be careful of burns when handling the
water drain valves or other hot components of the machine.
NOTE: With increased cooling water temperature, the volume of the cooling water ex-
pands. Therefore, be sure to slightly open the valve at the cooling water outlet side of
the chiller-heater.
