York YMAA 0045 Installation Manual page 16

SECTION 2 – PRODUCT DESCRIPTION
COOLING MODE
Low pressure liquid refrigerant enters the evaporator BPHE and
is evaporated and superheated by the heat energy absorbed from
the chilled liquid. Through 4-way valve, suction accumulator,
the superheated low pressure vapor enters the compressors and
HEATING MODE
Two-phase refrigerant liquid enters RTPF (round tube and plate
fin) coils and fully evaporated there by absorbing the heat from
the flowing air driven by the EC fan. Through 4-way valve
and accumulator, superheated low suction vapor enters the
compressor(s). The compressors rework to compress vapor to
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is compressed to high pressure. The high pressure vapor is fed
to the ambient coils and fans, via the four way reversing valve,
where heat is removed. The fully condensed and subcooled
liquid passes through the electronic expansion valve where
pressure is reduced and turned into two-phase refrigerant
mixture to make chilled water in evaporator BPHE.
FIGURE 2 – COOLING FLOW DIAGRAM
higher pressure, which flow into BPHE (as a condenser) and
condensed into refrigerant liquid by rejecting the heat to the
flowing water to make hot water. The subcooled refrigerant
liquid goes through EEV and re-enters into RTPF coils (as
evaporator) to repeat the circulation.
Email: sales@cookeindustries.co.nz
FORM NO.:6U6K-B01E-NB-EN
JOHNSON CONTROLS
Web: www.cookeindustries.co.nz