Filter Drier; Capillary Tube; Alu-Dry Module; Hot Gas By-Pass Valve - Beko DRYPOINT RA 200/AC NA Operating Manual

Technical description
5.9.

Filter Drier

Traces of humidity and slag can accumulate inside the refrigerating circuit. Long periods of use can also produce
sludge. This can limit the lubrication efficiency of the compressor and clog the expansion valve or capillary tube. The
function of the Filter Drier, located before the capillary tubing, is to eliminate any impurities from circulating through the
system.

5.10. Capillary Tube

It consists of a piece of reduced cross section copper tubing located between the condenser and the evaporator, acting
as a metering device to reduce the pressure of the refrigerant. Reduction of pressure is a design function to achieve
optimum temperature reached within the evaporator: the smaller the capillary tube outlet pressure, the lower the
evaporation temperature.
The length and interior diameter of the capillary tubing is accurately sized to establish the performance of the dryer; no
maintenance or adjustment is necessary.

5.11. Alu-Dry Module

The heat exchanger module houses the air-to-air, the air-to-refrigerant heat exchangers and the demister type
condensate separator. The counter flow of compressed air in the air-to-air heat exchanger ensures maximum heat
transfer. The generous cross section of flow channel within the heat exchanger module leads to low velocities and
reduced power requirements. The generous dimensions of the air-to-refrigerant heat exchanger plus the counter flow
gas flow allows full and complete evaporation of the refrigerant (preventing liquid return to the compressor). The high
efficiency condensate separator is located within the heat exchanger module. No maintenance is required and the
coalescing effect results in a high degree of moisture separation.

5.12. Hot Gas By-pass Valve

This valve injects part of the hot gas (taken from the discharge side of the compressor) in the pipe between the
evaporator and the suction side of the compressor, keeping the evaporation temperature/pressure constant at approx.
36° F (+2 ° C). This injection prevents the formation of ice inside the dryer evaporator at every load condition.
ADJUSTMENT
The Hot Gas By-pass Valve is adjusted during the manufacturing testing
phase. As a rule no adjustment is required; anyway if it is necessary the
operation must be carried out by an experienced refrigerating engineer.
WARNING!
the use of ¼" Schrader service valves must be justified by a real
malfunction of the refrigerating system. Each time a pressure gauge is
connected, a part of refrigerant is exhausted.
Without compressed air flow through the dryer, rotate the adjusting
screw (position A on the drawing) until the following value is reached:
Hot gas setting (R404A) :
20
temperature 33° F (+1 / - 0 ° F)
pressure 75.4 psig (+1.5 / -0 psi)
temperature 0.5 ° C (+0.5 / -0 ° K)
pressure 5.2 barg (+0.1 / -0 bar)
DRYPOINT RA 200-1250 NA
A
-
+
DRYPOINT RA 1500-2500 NA
8 mm
5/16 in.
A
+
DRYPOINT RA 200 – 2500 NA
4 mm
5/32 in.
-