Blue Box KAPPA V SR Installation, Operating And Maintenance Manual Download

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Blue Box 29

4.9 WATER FLOW RATE TO EVAPORATOR

The nominal water flow rate is based on a 5 °C temperature difference between inlet and outlet in relation to the
supplied cooling capacity.

The maximum permissible flow rate is that which results in a temperature difference of 3 °C: higher flow rates will
lead to excessive pressure drops and could damage the evaporator.

The minimum permissible flow rate is that which results in a temperature difference of 8 °C or a pressure drop of
no less than 10 kPa: lower flow rates will lead to excessively low evaporation temperatures with consequent
tripping of safety devices and shutdown of the unit.

4.10 CHILLER WATER TEMPERATURE (summer cycle)

The minimum evaporator leaving water temperature is 6 °C; for lower water temperatures at the evaporator
outlet refer to section 6.6.
The maximum water temperature at the evaporator inlet is 20 °C. In the case of higher temperatures specific
solutions are necessary (dual circuits, three-way valves, by-pass, storage tanks): consult the Bluebox Engineering
Department to discuss the most suitable solution for your application.

4.11 HOT WATER TEMPERATURE (winter cycle)

The minimum water temperature at the condenser inlet, once the system is operating in steady state conditions,
must not be lower than 28 °C: lower values could result in operating anomalies of the compressor with the
consequent risk of compressor breakdown.
The maximum water temperature at the condenser outlet must not be higher than 47 °C. In the event of higher
temperatures the safety devices will trip causing the unit to shut down.

4.12 AMBIENT AIR TEMPERATURE

The units are designed and built to operate with ambient air temperatures within the limits shown on the operating
limits diagrams. Contact Bluebox if the unit is required to operate at different ambient temperatures.
It should be noted that the performance of heat pump units decreases significantly at lower ambient temperatures.
(below 0 °C).
The units can be optionally equipped with an electric element for heating the evaporator. The heater cuts in,
when the machine is switched off, if the water temperature in the evaporator falls below the freeze protection
calibration temperature.

4.13 FAN SPEED CONTROL (optional)

If the unit is required to operate at ambient air temperatures less than 15 °C a fan speed controller must be
included. With fan speed control the unit can function correctly, at low ambient temperatures, by reducing the air
flow supplied to the condenser so that it operates within acceptable parameters.
This device can also be used to reduce unit sound levels as the ambient ait temperature reduces (for instance
during the night).

This control is calibrated and factory tested.

Warning: speed control calibration settings must not be altered. If it
proves necessary to alter speed calibration settings, this task must be
entrusted to a skilled engineer, who should refer to the attached instruction
sheet.