EPSILON-CF IOM.pdf - Industrial Air

6.15 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.
6.16 OPERATION IN LOW AMBIENT AIR TEMPERATURE CONDITIONS (OPTION)
As ambient air temperature decreases it is possible to maintain the necessary condensation pressure for correct
operation of the cooling cycle within the machine operating range by adjusting the cooling air flow through
the condenser.
Condensation pressure control is only active when the machine is operating in cooling mode.
Condensation control is disregarded during heat pump mode operation.
Condensation pressure regulation is achieved by a modulating damper that varies the air volume over the
condenser coil in accordance with the condensing pressure read by the pressure transducers.
6.17 OPERATION WITH LOW TEMPERATURE CHILLED WATER AT EVAPORATOR
Units from the normal production range are not designed to operate
with chilled water temperatures lower than those indicated in the
operating limit diagrams, at the evaporator outlet. To operate outside
this limit the unit may require structural modifications. If this is
necessary contact Bluebox.
With temperatures lower than those shown in the operating limit diagrams, the hydraulic circuit should be filled
with a suitable water and antifreeze solution. In such cases the service thermostat and the freeze protection
thermostat must be reset:
These calibrations are normally factory set.
The ethylene glycol percentage must be selected in relation to the required chilled water temperature.
See table 2.
In the case of ST versions with a glycol content greater than 30%
pumps with special seals must be specified at the time of the order.
TABLE 2 - FREEZING POINT FOR WATER-ANTIFREEZE MIXTURES
LIQUID OUTLET TEMPERATURE
OR MINIMUM AMBIENT TEMERATURE (°C)
+0° -5° -10° -15° -20° -25° -30° -35° -40°
FREEZING POINT (°C) -5° -10° -15° -20° -25° -30° -35° -40° -45°
ANTIFREEZE % BY WEIGHT
ETHYLENE GLYCOL 6 22 30 36 41 46 50 53 56
PROPYLENE GLYCOL 15 25 33 39 44 48 51 54 57
METHANOL 8 14 20 26 30 34 38 41 45
CALCIUM CHLORIDE 9 14 18 21 24 26 27 28 30
TEMPER. –20 T -20°C —
TEMPER. –40 T -40°C —
TEMPER. –60 T -60°C
TIFOXITE 40 50 60 63 69 73 —
FREEZIUM 10 20 25 30 34 37 40 43 45
PEKASOL 50 50 59 68 75 81 86 90 —
Air Blue • 21