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DuPont SUVA® Refrigerents Service Manual
Compressor condensation
In order to recuperate the refrigerant vapour at the evaporator outlet, we complete the previous set-up as follows (Fig. 3):
Summary
A refrigerant installation is essentially made up of the following components:
Elements
Roles
Receiver
Reserve of liquid refrigerant allowing to
compensate for the variations (leaks or
cooling demand) Should be able to contain all the refrigerant in the system.
Accumulator
Vessel on the suction side of the compressor containing a “buffer” volume of
superheated vapour. Allows for variations in evaporator load and protects
the compressor.
Evaporator
Heat exchanger – absorbs heat from the
ambient medium (cools the service
medium) and allows evaporation of the
refrigerant.
Compressor
A gas pump causing the refrigerant
vapour to change from low pressure to
high pressure.
a) Vapour leaving the evaporator enters the compressor, with
the inlet valve open.
Condenser
Heat exchanger – rejects heat from the
system. Condensation of the refrigerant
occurs in the condenser.
b) The piston goes down and the total volume of the chamber is filled with vapour.
Expansion Device
Allows the refrigerant to go from high to
low pressure and regulates the flow into
the evaporator.
Fig. 3
Absorbed heat
Rejected heat
Evaporator
7 bar
1 bar
7 bar
Condenser
Compressor
Ambiant temperature
15 ϒC
c) The piston goes up, the inlet valve closes, the pressure in
the chamber increases to 7 bar, the exhaust valve opens and
the gas at high pressure is let out.
Diagrams
d) The high pressure gas enters the second heat exchanger
and gives away heat to the ambient medium. Since the gas is
giving heat away, it changes from vapour to liquid.
Vapour is condensed in this heat exchanger called a condenser.
e) The liquefied refrigerant is returned to the storage cylinder and the cycle is completed.
Water
a) Temperature/Enthalpy
Fig. 4
Temperature
ϒC
D
Saturated
liquid
100 ϒC
liquid
0 ϒC
12
A
0 kJ
B
C
Saturated
vapor
Enthalpy
418 kJ
2671 kJ