McQuay seasoncon ALP-067A, Установка и техническое обслуживание

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REFRIGERANT PIPING
General
McQuay type ALP condensing units are adaptable to either chilled
water or air handling air conditioning applications. The only re-
striction on applications is that the evaporator be selected for a
system using refrigerant 22.
Evaporator Above Condensing Unit
Figure 6 shows an installation where the evaporator is installed
above the condensing unit. It is shown for an air handling instal-
lation but all components shown are recommended for chilled water
installations except that a refrigerant distributor is not usually
required for shell-and-tube evaporators.
FIGURE 6 EVAPORATOR ABOVE CONDENSING UNIT
Legend
a Filter-drier
b Solenoid valve
Sight-glass/moisture indicator
Thermal expansion valve
e Suction line, pitched toward compressor
f Liquid line
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Vibration absorber
Notes:
1. Piping shown is for one circuit only, second circuit is similar.
2. All piping & piping components are by others.
Evaporator Below Condensing Unit
Figure 7 shows an installation where the evaporator is installed be-
low the condensing unit. It is shown for an air handling installa-
tion but all components shown are recommended for chilled water in-
stallations except that a refrigerant distributor is not usually re-
quired for shell-and-tube evaporators.
Mote that a double suction
riser is shown for this arrangement.
Risers "A + B" are sized so that their combined cross-sectional in-
ternal area will allow full load unit operation without excessive
pressure drop (see notes, Table 4). Riser "B"
is sized to provide
adequate suction gas velocity for proper oil return at minimum load
conditions. This riser becomes effective only when the trap shown
in riser "A"
fills itself with oil.
It should be emphasized that
the trap shown in riser "A"
should be designed to contain a minimum
internal volume to keep the total system oil requirements at a mini-
mum. Table 4 gives recommended line sizes for both single and double
suction lines and for liquid lines.
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