Lochinvar Copper-fin II/IIE 402 - 2072 - Manual (Page 22)

Control modes
SH controlling sensor (boiler only)
The SH controlling sensor parameter selects the sensor the
control will use to regulate the boiler firing rate. The sensor
selections are as follows: The outlet sensor regulates the
firing rate based on the outlet water temperature of the unit
and the inlet sensor regulates the firing rate based on the
inlet water temperature of the unit. If the outlet sensor is
selected, and the optional system supply sensor is connected,
the control will regulate the firing rate based on the system
sensor temperature. If the inlet sensor is selected, and the
optional system return sensor is connected, the control will
regulate the firing rate based on the system return sensor.
When programmed to use the inlet sensor, a system supply
sensor must be installed for proper operation. If a 3-way
valve is installed for low temperature protection, a system
return sensor must be installed as well. The default sensor is
the Outlet Sensor.
Enable input (active / inactive)
The boiler or water heater can receive a call for heat in
two different ways. First, an external contact (like a tank
thermostat) or sensor (like a tank sensor) can generate
a call for heat. Second, the 0-10Vdc voltage from a BMS
can be used to generate the call for heat, as well as provide
the setpoint or modulation level. On boilers, the external
contact is connected to the Stage 1 input on the low voltage
connection board. On water heaters, the external contact is
connected to the Tank Thermostat input on the low voltage
connection board. When a tank sensor is connected, the Tank
Thermostat input is not used. When the call for heat comes
from an external contact or tank sensor, the enable input
must be set to active. When the call for heat comes from the
0-10Vdc input, the enable input must be set to inactive. The
default setting is Active. Can only be set to inactive when BMS
input is set to active.
BMS input (active / inactive)
When the building management input is enabled, the
control modulates the unit or the cascade based on the
voltage on the 0-10V input on the connection board. The
0-10V input may control either the modulation of the
unit(s), or the setpoint. The default value is Inactive. See
menu Section J to adjust the parameters that control the
BMS operation.
Cascade (active / inactive)
Boilers or water heaters may be part of a group of units
sequenced together. When so connected, each heater must
be programmed to operate as part of the Cascade. This is
done by setting the Cascade to Active. The default value
is Inactive.
Sequencer (active / inactive) (boiler only)
The individual stages in the heater can be controlled
separately with an external sequencer.
ModBus (active / inactive)
When the optional ModBus board is installed, the heater
can be monitored and controlled by a Building Control
System (BCS). If the heater is to be controlled through
ModBus this parameter must be set to ACTIVE. The
default value is Inactive.
ModBus timeout
When the heater is being controlled or is receiving
temperature readings through ModBus, the information
sent to the heater must be refreshed periodically. If the
heater does not receive new information after a timeout, it
will revert to local temperature readings and control. This
prevents the heater from running for too long should the
ModBus connection be lost. The range of this parameter is
0 to 120 seconds. The default value is 10 seconds.
1
Service
Copper-fin II/IIE Boiler and Water Heater Service Manual
22