SRC Service Manual
Revision 02
Aug 2007
Page 16 of 56
3.3.1 Compressor
All models are equipped as standard with hermetic
refrigeration compressors, which are maintenance-free
and installed on vibration damping mountings, and are
protected by internal thermal overload protection, and
over current relays.
The compressor reduces the pressure in the evaporator
ensuring the refrigerant evaporates at the correct
pressure (and therefore temperature). It compresses
the evaporated refrigerant and sends it to the
condenser.
Piston Compressor:
SRC-150 to 200
Scroll Compressor:
SRC-250 to 1000
The SRC-150 to 200 dryers feature piston compressors
with a single phase motor.
SRC-250 to 1000 dryers are fitted with compliant scroll type compressor with a three phase motor.
Compliant scroll compressors are not damaged by liquid returns, and as such, they do not require pre-
heating upon start-up.
They also offer significant advantages in terms of energy savings, reliability, high efficiency and quiet
operation.
3.3.2 Condenser & Fan
The condenser cools the refrigerant causing it to
condense back to a liquid.
All models are offered with an air-cooled condenser,
which uses ambient air as the cooling medium.
The condenser comprises one or more finned coils
(copper pipes, aluminium fins) across which air is blown
by one or more axial fans.
The axial fans are supplied with external rotor electric motors and die-cast aluminium blades,
complete with protection grilles. On the SRC-250 to 1000, the electric motors of the fans are protected
by thermal and over-current relays.
On the SRC-250 to 1000 the condensing coils feature a wire mesh pre-filter. This significantly reduces
dirt accumulation on the condenser, thereby reducing the need to shut the dryer down for condenser
cleaning, while at the same time reducing energy consumption.
In addition, in the SRC-250 to 1000, the condensing section is completely separated from the rest of
the dryer, thereby allowing maintenance even when the dryer is in operation.
The heat absorbed by the refrigerant in the Coolant-to-Refrigerant Heat Exchanger and produced
during compression, is rejected to the ambient in the condenser. If the condenser is unable to reject
all the heat absorbed (i.e. due to fouling), the refrigerant system will overheat and over pressure,
resulting in shutdown.
