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Superior Valve Company

Replaceable Suction Filter
• On many parallel systems, the Superior Valve Co.
suction filter is installed.
Table 25. Type F Filter
Replaceable Cartridges
Shell Catalog IBCA Cartridge Filter
No. No. No. OD (in) Area (in2)
2CFA F25A 51071 1 - 23/32 66
3CFA F35A 51072 2 - 5/8 115
4CFA F45A 51073 3 - 17/32 189
5CFA F55A 51074 4 - 1/16 270
Table 26. Type DF (for cleanup)
Replaceable Cartridges
Shell No. Catalog IBCA Cartridge Filter
No. No. No. OD (in) Area (in2)
2CFA DF25A 51053 1 - 23/32 66
3CFA DF35A 51059 2 - 5/8 115
4CFA DF45A 51060 3 - 17/32 189
5CFA DF55A 51061 4 - 1/16 270

Alco Controls

Alco Suction Filter
Comparable to the Superior suction filters and
interchangeable cores.
Table 27. Type AF Filter
Replaceable Cartridges -
Shell Filter Cartridge Filter Area
No. Core OD (in) Area (in2)
BTAS-2 A2F 1 - 29/32 66
BTAS-3 A3F 2 - 3/4 115
BTAS-4 A4F 3 - 3/4 189
BTAS-5 A5F 4 - 5/16 270
Table 28. Type AFD (for cleanup)
Replaceable Cartridges -
Shell Filter Cartridge Filter Area
No. Core OD (in) Area (in2)
BTAS-2 A2F-D 1 - 29/32 66
BTAS-3 A2F-D 2 - 3/4 115
BTAS-4 A2F-D 3 - 3/4 189
BTAS-5 A2F-D 4 - 5/16 270
Head Pressure Control
In a system with variable pressure control the receiver
pressure is maintained at the desired pressure by supplying
discharge gas to it through an adjustable outlet regulator.
Further power savings may be realized by directing only the
hot gas to the top of the receiver to minimize the mixing of
cold liquid and hot gas. As a result subcooled liquid is fed to
the evaporators resulting in increased refrigeration effect and
efficiency. Also, the amount of hot gas, that would otherwise
condense to wary liquid, is reduced and a lower cost, smaller
regulator can be used. In general, only one third of bypass is
needed compared to mixing the gas and liquid entering the
receiver.

Valve Functions

Referring to the Figure above, Valve A is an Inlet Pressure
Regulator in the liquid drain line from the condenser, and
senses the condenser pressure. The regulator closes as the
condenser pressure drops below the set point, thus back-
flooding the condenser and reducing the inside surface area
available for condensing.
Valve B is and Outlet Pressure Regulator in the bypass line
from compressor discharge to the condenser liquid drain line.
This valve senses the receiver pressure and opens when this
pressure drops below the set point, thus maintaining the
receiver pressure.
Valve C is an In-line Check Valve in the liquid drain line to
prevent higher pressure from backing up into the condenser
during low ambient conditions when the compressor is idle.