Outdoor Temperature Sensor; Central Heating Thermostat - Dunkirk DMG-240 Installation, Operation & Maintenance Manual

Sensors supplied with this product are proprietary
Note to the manufacturer. Use of after market sensors
will result in diminished performance.
8.9 1 K Ohm (1K Ω) Outdoor Temperature Sensor
Outdoor Temperature
Flow Temperature
P1 - Supply temperature (maximum)
P25 - Supply temperature (minimum)
P26 - "WWSD" (Warm Weather Shutdown)
P27 - Outdoor temperature (default)
If outdoor temperature sensor is connected, heating curve can
be adjusted. Setting can be modified using parameters - P1,
P25, P26 and P27.
• 1K Ω
Outdoor Sensor, if used.
A. Provided with boiler.
B. Locate 1 K Ω outdoor sensor to protect against
wind and direct sunlight. Mounting instructions
provided with sensor.
C. Maximum wire length is 100 ft (30m) for 22 ga.
wire, or 150 ft (45m) for 18 ga. wire.
D. Connect wires to OUTDOOR SENSOR terminals.
Wires are interchangeable.
E. Outdoor temperature sensors are a boiler accessory.
Where there is an on/off thermostat, boiler will control
the temperature with set point of the internal heating
curve.

8.10 Central Heating Thermostat

A. If a room thermostat with an anticipator is used,
parameter P5 must be adjusted.
B. Install thermostat in frequently occupied room.
C. Connect 2 wire dry contact room thermostat to
ON/OFF-OT terminals of boiler's control board
connection. Note :ON/OFF-OT terminals are NOT
able to supply 24V to the thermostat.
D. Use thermostat or boiler system control with dry
contacts related 0.5 amps @ 120 VAC. Boiler
control does NOT provide 24 VAC power to central
heating thermostat.
E. Locate and install thermostat per manufacturer's
instructions. Maximum wire length is 330 ft (100m)
for 22 ga. wire.
F. Connect wires to on/off - OT terminals. Wires are
interchangeable.
G. Boiler is not suitable for Nest type thermostat
without the use of an isolation relay, such as Argo
IR-882.
8 - ELECTRICAL CONNECTIONS
FIGURE 8-10 1k Ω Outdoor Temp Sensor
FIGURE 8-11 1k Ω Outdoor Temp Sensor Chart
Note
Note
45
1 K Ω
Use dry contact for wires to On/Off OT terminal.
E33 error code is displayed if voltage is sent
back to the control board. If error is not
corrected for extended period of time, this
voltage can permanently damage control board.
If room thermostat with anticipator is used,
parameter P5 must be adjusted.
P/N 240011656, Rev. E [07/30/2018]