Sullair RD Series, Руководство пользователя и обслуживания

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RH SERIES—HIGH TEMPERATURE SECTION 2
14
2.4.9 R
EFRIGERANT CIRCUIT
:
The refrigerant circuit can be divided into 3 parts:
1. Low pressure section with an evaporator
(heat exchanger)
2. High pressure section including: Condenser,
liquid receiver, (if installed) and the filter
dryer.
3. Control circuit including: Compressor, expan-
sion valve, by-pass valve (if installed), fan
pressure switch, safety high pressure switch.
2.4.10 T
HE
R
EFRIGERANT CIRCUIT OPERATES
AS FOLLOWS
:
1. The compressor compresses gaseous refrig-
erant.
2. The hot refrigerant gas condenses in the
condenser. Being liquefied, it is stored in the
liquid receiver (if existing).
3. The liquid is taken out of the storage receiver
vessel and injected into the evaporator (heat
exchanger) by an expansion valve. This
expansion valve is protected by a filter dryer,
that retains particles and humidity that could
be in the circuit.
4. The injected liquid fills in the refrigerant sec-
tion of the Air-Refrigerant heat exchanger
and evaporates due to the heat from the
incoming air. The gaseous refrigerant is
sucked in the compressor and the cycle car-
ries on.
5. In order to keep the evaporation pressure
steady, and thus the refrigerant temperature
in the heat exchanger, a by-pass valve
injects hot gaseous refrigerant into the cir-
cuit. On certain dryers, an automatic pres-
sure expansion valve regulates this process.
2.4.11 C
OMPRESSED AIR CIRCUIT
1. The hot, saturated, compressed air from the
compressor is forced into the air-cooled
after-cooler where it is pre-cooled to approxi-
mately ambient temperature.
2. This pre-cooled compressed air enters the
high-efficiency moisture separator where
condensed moisture is stripped from the air
stream and purged out via the electronic
timer drain.
3. The air then enters the first stage of the heat
exchanger (air to air pre-cooler/re-heater)
where the outgoing chilled air cools the
incoming hot air. This energy saving heat
exchanger provides significant advantages,
such as a reduction of the heat load imposed
on the refrigerant compressor and con-
denser, re-heating the outlet air, and prevent-
ing condensation of moisture in the plant air
distribution lines.
4. From the air-to-air heat exchanger, air enters
the air-to-refrigerant heat exchanger where
further cooling occurs and the air tempera-
ture is reduced to the desired pressure dew
point (PDP). As the air is cooled, the mois-
ture condenses into a liquid and is then sep-
arated in the integrated high efficiency
separator and discharged through the con-
densate drain.
5. The cooled air then re-enters the air-to-air
heat exchanger, in a direction opposite to the
flow of the warm, saturated incoming air and
pre-cools the hot air. During this process the
outgoing air is reheated thereby minimizing
the chances of moisture condensation in the
compressed air distribution lines.