3.
APPLICATIONS
3.1. COMPENSATED VALVE CONTROL
This compensator application operates a 3 port mixing valve to control the flow
temperature of the system based on the outside temperature. A room sensor is
optional and is used to trim the flow temperature and not to control it. The way room
influence works can be selected to suit your needs. It need not be used. The flow
temperature can be adjusted by 3ºC for every 1ºC the room temperature is above or
below the daytime space temp set value (SVd).
If the CSC 5352 is used then the clock determines whether the compensator
operates in day or Night Set-Back (NSB) mode. The CSC can be set to allow the
heating i.e. pump, valve etc. to run at reduced set points or turn off during the off
periods. When in NSB mode the action of Room Influence is adjusted to work only in
a negative fashion as to reduce the flow temperature. The flow temperature will be
lowered by 3
°
C for every 1
°
C the room temp is above the relaxed set point (SVn).
The compensator has 2 compensation ratios and a high limit function to prevent
excessive set points occurring.
Out of hours, If the outside temperature drops below an adjustable frost setting,
defaulted to 0
°
C, the pump is enabled and “Auto 1” is displayed on the controller.
The CSC will resume normal operation when the outside temperature increases by
2
°
C. If a space sensor is used then this will also provide frost protection to protect
the building fabric. The low space temperature is adjustable but is normally set to
10
°
C. If this limit is passed then the heating will come on in boost to ensure the
fastest possible relief. “Auto 3” will be displayed on the CSC during this period. The
frost condition will be removed when the space temperature has risen by 2
°
C. If for
any reason, the flow temperature should fall below 5
°
C the CSC will act to remove
the possibility of frost. The controller will start the pump and open the valve to raise
the water temperature of the system, the CSC will remain in this condition for 30
minutes. When this event occurs during a standby period if not day or NSB, the
CSC will display "Auto 2" for the period. If your CSC doesn’t have a time clock, then
Frost Protection is not included as the controller does not control the pump. All Frost
Protection must be provided by other interlocked devices such as thermostats.
If under floor heating is used, please remember to check the high limit setting so as
not to allow excessive flow temperatures.
Pump
Time switch
version only
(Optional)
(Flow
Temp)
Boiler
Fig.1
* A control and safety high limit thermostat
must be used on the boiler
October, 03
CSC USER GUIDE
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