12
IM 1131-2
Refrigerant Piping
Table 4: Recommended Horizontal or Downflow Discharge Line Size, R-410A
Typical Arrangements
Figure 7
illustrates a typical piping arrangement involving a
remote air-cooled condenser located at a higher elevation than
the compressor and receiver. This arrangement is commonly
encountered when the air-cooled condenser is on a roof and the
compressor and receiver are on grade level or in a basement
equipment room.
Figure 8
illustrates another very common application where
the air-cooled condenser is located on essentially the same
level as the compressor and receiver. The discharge line piping
in this case is not too critical. The principal problem
encountered with this arrangement is that there is frequently
insufficient vertical distance to allow free drainage of liquid
refrigerant from the condenser coil to the receiver.
Notice, in both illustrations, that the hot gas discharge line is
looped at the bottom and top of the vertical run. This is done to
prevent oil and condensed refrigerant from flowing back into
the compressor and causing damage. The highest point in the
discharge line should always be above the highest point in the
condenser coil. It is advisable to include a purging vent at this
point to extract non-condensables from the system.
The receiver is used when it is desired to have refrigerant
storage capacity in addition to the pumpdown capability of the
condenser.
Figure 1: Condenser Above Compressor and Optional Receiver Installation
Up to
Up to
Up to
Up to
Up to
50 Equiv. Ft
75 Equiv. Ft
100 Equiv. Ft
125 Equiv. Ft
150 Equiv. Ft
WGZ030
1 3/8"
1 1/8"
1 1/8"
1 1/8"
1 1/8"
1 1/8"
WGZ035
1 3/8"
1 3/8"
1 3/8"
1 3/8"
1 3/8"
1 3/8"
WGZ040
1 3/8"
1 3/8"
1 3/8"
1 3/8"
1 3/8"
1 3/8"
WGZ045
1 3/8"
1 3/8"
1 3/8"
1 3/8"
1 3/8"
1 3/8"
WGZ050
1 3/8"
1 3/8"
1 3/8"
1 3/8"
1 3/8"
1 3/8"
WGZ055
1 3/8"
1 3/8"
1 3/8"
1 3/8"
1 3/8"
1 3/8"
WGZ060
1 3/8"
1 3/8"
1 5/8”
1 5/8”
1 5/8”
1 5/8”
WGZ070
1 3/8"
1 3/8"
1 5/8”
1 5/8”
1 5/8”
1 5/8”
WGZ080
1 5/8”
1 5/8”
1 5/8”
1 5/8”
1 5/8”
1 5/8”
WGZ090
1 5/8”
1 5/8”
1 5/8”
1 5/8”
1 5/8”
1 5/8”
WGZ100
1 5/8”
1 5/8”
1 5/8”
1 5/8”
1 5/8”
1 5/8”
WGZ115
1 5/8”
1 5/8”
1 5/8”
2 1/8"
2 1/8"
2 1/8"
WGZ130
1 5/8”
1 5/8”
2 1/8"
2 1/8"
2 1/8"
2 1/8"
WGZ150
2 1/8"
2 1/8"
2 1/8"
2 1/8"
2 1/8"
2 1/8"
WGZ170
2 1/8"
2 1/8"
2 1/8"
2 1/8"
2 1/8"
2 1/8"
WGZ200
2 1/8"
2 1/8"
2 1/8"
2 1/8"
2 1/8"
2 5/8"
Recomm ended Discharge Line Sizes
Conn. Size
at Unit
Unit Model
Condenser
Relief Valve
Check Valve
Purge Valve
Discharge Line
Loop
Receiver
Receiver
Bypass
To
Evap.
Preferred
Subcooler
Hook-up
Relief Valve
(Vent to O utdoors
or to Condenser Side
of Liquid Line
Check Valve)
Pitch
Check
Valve
Subcooler