SRC Service Manual
Revision 02
Aug 2007
3.2.2 Coolant-to-Refrigerant Heat Exchanger
The Coolant-to-Refrigerant Heat Exchanger is common to both the Coolant Circuit and the
Refrigeration Circuit. It uses cold refrigerant to cool the water/glycol mixture to the desired
temperature. The Coolant-to-Refrigerant Heat Exchanger is also known as the “Evaporator” as this is
where evaporation of the liquid refrigerant takes place. The Heat Exchanger is positioned inside the
coolant tank (it cannot be removed). This design allows several significant advantages over a
separate tank and heat exchanger design:
•
the evaporator is protected and thermally isolated,
•
the exchange of heat between the evaporator and the surrounding coolant further improves the
efficiency, and
•
the space saved means that the already compact dimensions of the dryer are reduced even
further.
On the SRC-150 through 500 the evaporator is a coaxial tube design. The outer tube is made of PVC
to allow it to expand without damage in the case of a system upset causing ice formation.
SRC-150 to 200 (Vertical)
SRC-250 to 500 (Horizontal)
On the SRC- 700 through 1000 the evaporator is a finned coil design, with copper pipes and
aluminium fins. This type of evaporator offers a high efficiency together with a special design which
creates a wide coolant flow path with a consequent low coolant velocity; the upside of this is a low
coolant-side pressure drop.
SRC-700 to 1000
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