Camus Hydronics Valiant FT VA0080, Manual

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When the mode of operation is set to CH Mode 0, no
outdoor sensor is needed. The boiler will wait in standby
mode until the Local/Remote switch, or the
ENABLE/DISABLE contact is closed; upon which the boiler
will use a PID algorithm to maintain the setpoint. The power
for the burner is PID regulated between the parameters
T_Supply
and
CH_Setpoint
which are found under the
menu ‘Boiler Parameters’ .
5.4.2 CH Mode 1: Outdoor Reset Operation with
Thermostat Control
An outdoor sensor is required when the mode of operation
is set to CH Mode 1. Once an outdoor sensor is connected,
the boiler automatically activates the parameter
Design_Supply_Max_Limit
. The Outdoor Reset Curve must
be designed by adjusting the parameters below.
Outdoor Reset Curve Parameters
Figure 33: Outdoor Reset Curve Parameters
DESIGN_SUPPLY_MAX_LIMIT: This is the parameter
which decides the maximum possible Setpoint the boiler will
try to reach along the curve. This is the upper Setpoint limit
of the curve.
DESIGN_SUPPLY_MIN_LIMIT:
This parameter sets the
minimum possible Setpoint the boiler will adjust to at the
lower end of the curve. This is the lowest Setpoint limit
along the curve.
In an Outdoor Reset mode, the boiler will adjust its Setpoint
in between the Maximum and Minimum Setpoints set by the
above two parameters.
The following 4 parameters need to be adjusted to adjust
the slope of the curve between the Boiler Maximum and
Boiler Minimum points.
Figure 34: Outdoor Reset Curve Parameters
DESIGN_SUPPLY_TEMP:
This parameter sets the higher
boiler Setpoint at the cooler end of the Outdoor
Temperature.
DESIGN_OUTDOOR_TEMPERATURE:
This parameter
sets the cold-end Outdoor Temperature reference point.
The two parameters above define the first reference point
to determine the slope of the Outdoor Reset Curve.
Figure 35: Outdoor Reset Curve Parameters
BASELINE_OUTDOOR_TEMP: This parameter sets the
lower boiler Setpoint at the warmer end of the Outdoor
Temperature.
BASELINE_SUPPLY_TEMP:
This parameter sets the
warm-end Outdoor Temperature reference point.