Boyd AAVID Kodiak H02 Series, Техническое руководство

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Kodiak  Recirculating Chiller Technical Manual
Manual# 820-0043 Rev N, 11/25/2019
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Many refrigeration systems, such as those used in household refrigerators, control the
temperature by turning the compressor on and off. This is a simple, inexpensive method of
controlling the cooling, but its temperature control is not precise and the frequent on-off cycles
cause wear on the compressor motor.
Boyd’s recirculating chillers use a better method for controlling the cooling rate: a hot-gas
bypass system. This employs a liquid line solenoid valve and a hot-gas bypass valve to meter
the refrigerant flow through the evaporator when refrigeration is needed. When the coolant
reaches its set point temperature, the liquid line solenoid valve closes, causing the hot-gas
valve to open. The hot-gas valve lets hot-gas from the compressor discharge into the
evaporator inlet, adjusting the temperature in the evaporator to maintain the correct coolant
temperature. When refrigeration is needed, the liquid line solenoid valve opens, the hot-gas
valve closes and the cycle starts again.
This hot gas bypass control method provides precise temperature control. It also minimizes
wear on the compressor motor, since the compressor runs continuously and does not
experience the stress of repeated cycling.