GESTRA Gestramat CW 41, Оригинальная инструкция по установке

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10
Task and function
Purpose
Cooling-water control valves are directly actuated
proportional controllers. They are used to maintain
a constant return temperature in a cooling-water or
cooling-solution return. The return temperature can
be adjusted.
This enables a higher return temperature and
therefore increased heat absorption by the cooling
water or cooling solution. The consumption of
coolant and energy is therefore reduced.
Cooling-water control valves also ensure the
demand-based supply of coolant to heat
exchangers connected in parallel.
The optional diaphragm actuator provides the
additional function of removing impurities. This
enables the equipment to be used with dirty or
untreated cooling water. The diaphragm actuator
can also be operated centrally. This way, you can
switch the diaphragm actuator on and off from a
control stand, for example .
Function
CW 41 and CW 41/4
The control unit consists of one (DN25), two (DN40,
DN50) or three (DN80, DN100) solids thermostats,
depending on the size of the equipment.
When the equipment becomes hot, the expansion
material in the thermostat (11) expands in volume.
When the return temperature increases, a pin is
pushed out of the thermostat. This lifts and
therefore opens the double cone (12) against the
pressure of the spring (3). The flow rate increases.
When the return temperature falls, the expansion
material in the thermostat shrinks in volume. The
spring pressure closes the double cone. The flow
rate falls.
A bleed flow is continually present, even when the
equipment is closed. The bleed flow enables the
equipment to react quickly to changes in return
temperature. You can regulate the bleed flow rate
using a setting screw (7).
In models with r-cone, the bleed flow is directed
through two holes in the double cone. In models
with s-cone, the bleed flow is directed via the lower
seat.
To set the desired return temperature, use the
adjuster (6). The currently set return temperature is
displayed on a scale on the adjusting key.