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• When the optional basin heaters are not included:
– Once ambient temperature drops below 35°F (1.7°C), water will remain in the basin
for 1 hour and then the water will be drained.
– The solenoid make-up valve will remain closed until the ambient temperature is
above 35°F (1.7°C) and when evaporative cooling is required.
• When optional basin heater(s) are included, the basin heater(s) turn on when the
Figure 10.
Optional Basin Heater(s)
following conditions are met:
– Spray water basin temperature drops below 40°F (4.4°C).
– Spray pumps are off.
– Sufficient water level in the basin.
• When the ambient temperature remains below 40°F (4.4°C), water will remain in the
basin for the duration of the user-defined time-based drain.
hCore
®
Heat Transfer Technology Freeze Protection
For protection against freezing of the hCore
®
Heat Transfer Technology (closed loop heat
transfer section), recommended methods are an industrial grade inhibited ethylene glycol
or propylene glycol solution. When the use of glycol is not practical, the system must be
designed to meet both minimum flow and minimum temperature requirements.
• See
Table 1
, for hCore
®
Heat Transfer Technology volumes for Nexus
®
Modular Hybrid
Cooler models.
• When a glycol solution is not utilized, operate the system to meet the following
conditions.
– Maintain the minimum recommended flow through the hCore
®
Heat Transfer
Technology at all times (see
Table 1
).
• Maintain a minimum heat load on the circulating fluid so that the temperature of the
fluid leaving the coil is not less than 45°F (7.2°C).
• To maintain the leaving fluid temperature at 50°F (10°C) when the process load is
extremely light or shut off, apply an auxiliary heat load to the circulating fluid and
adjust the flow to ensure that fluid leaving the coil maintains the minimum required
temperature.
NOTE:
For the units with the heater
option installed, units are shipped
with two separate control panels –
one iPilot
®
Control System and one
heater control panel (which must be
interconnected).
WARNING:
For basin and heater
maintenance – switch off both of
the control panels and lock and tag
out the main disconnects
.