ECR International Dunkirk DCB-100, Installation, Operation & Maintenance Manual

Page: 49 / 143

45
8 - ELECTRICAL CONNECTIONS
A. Connect Room Thermostat
• turn power off to boiler;
• access terminal block M2 ;
• connect room thermostat to terminals 6(R)-7(W)-
8(C) ; Do not apply voltage between 2 terminals. Dry
contact only.
• turn boiler power on;
• verify room thermostat operates per room thermostat
manufacturer instructions.
NOTE: maximum load allowed is 10 mA
Dry contact room thermostats from various manufacturers
can be attached to boiler control PCB.
FIGURE 8-4 Room Thermostat Connections
8.5 Install Room Thermostat
Install room room thermostat on inside wall. Do not install
where it will be influenced by drafts, hot or cold water pipes,
lighting fixtures, television, sun rays or near a fireplace.
Dry contact only - do not apply 24 volts between 6 and 7.
A
Room End
Switch
8.6 Optional Outdoor Air Sensor (OAS) Electrical
Connections
A. 1K Ohm (1K
Ω) Optional Outdoor Air Sensor (OAS)
To connect this accessory, see Figure 8-5, terminals 4-5, and
instructions supplied with
1K Ω
sensor.
Note
Sensors used for this boiler are proprietary to
the manufacturer. Use of after market sensors
will diminish boiler performance.
FIGURE 8-5 Outdoor Sensor Connections
1K Ω
B. Setting "Kt" Climate Curve
1.
Boiler automatically recognizes OAS sensor when wired to M2
terminal block. Display changes to show current default “ Kt ”
value (80). Note display value.
2.
When operating in CH mode, boiler setpoint is determined
by the Kt value selected and actual outside air temperature.
Refer to applicable °F (or °C) chart, ( pg. 46 ) for setpoint
information.
3.
When OAS is installed, pressing or buttons will no
longer display boiler CH setpoint temperature. It now displays
Kt value, which can range from 10 to 90.
• Select Kt range which will satisfy the desired boiler delivery
temperature based on outdoor temperature range expected
for your location. For example: if you need 176°F water
when the outside temperature is 20°F and colder, select 35
for your Kt setting.
• Restrict the upper limit of the Kt curve by using Parameter
P16 to set the maximum boiler water temperature. P16
Default is 176°F.
• To change”default” Kt value on boiler control use or
CH Heating buttons.
4.
When scrolling has stopped, boiler will automatically “SAVE”
value as new Kt default value and automatically return to CH
mode when no Kt adjustment activity is sensed. Kt values
can be changed in +/- 1 point increments.
5.
To return, to verify or change current Kt “default value,
depress one of the CH setpoint adjustment buttons (once),
or , while in any heating or standby mode. Adjust Kt
value to obtain desired comfort level.
240013501 REV A [03/15/2022]