JOHNSON CONTROLS
157
SECTION 7 – MAINTENANCE
FORM 155.32-ICOM1.EN.GB
ISSUE DATE: 10/13/2017
7
STORAGE METHOD OF THE COOLING
WATER DURING HEATING OPERATION
PERIOD
Do NOT operate the cooling water pump during op-
eration 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 fol-
lowing 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 freezing. (In case
there is concern of freezing, apply an insulation
material to the cooling water piping.
2. The cooling tower is installed at the high level
(height) of the chiller-heater. (If not, the high tem-
perature water could flow into the cooling tower.)
3. Lining pipe is not used for the cooling water pip-
ing system. (If you use the lining pipe, use a heat
-resistant lining pipe.)
Do NOT leave the any poor quality cool-
ing water in the Absorber and Condenser
tubes. If you do, the heat transfer tubes
will be at high risk of corrosion.
Cooling water temperature can rise up to
approximately 80 °C due to the residual
heat during heating operation. Be careful
of burns when handling the water drain
valves, etc.
With the increased cooling water tem-
perature, the volume of the cooling water
expands. Therefore, be sure to slightly
open the valve at the cooling water outlet
side of the chiller-heater.
