Dunkirk 95M-200 Parameter Manual page 8

hybrid systems, with finned tube radiation and
radiant slab, provide additional low temperature
protection for the radiant portion of the system,
because Parameter 4 (T1 Top) is likely to be set
higher than on a radiant-only system.
IMPORTANT: Many slab-type radiant systems won't
require boost. This function can be disabled with a
parameter setting of "0."
BOOST OPERATION
1. In outdoor reset operation (outdoor sensor
connected), the boiler control automatically
increases the target outlet water temperature if a
call for heat exceeds a time equal to Parameter
11 (factory default of 30 minutes.
2. At each interval of Parameter 11 of a continuous
call for heat, the control module increases the
target temperature by 18° F.
3. The control module will continue increasing
target temperature until it reaches the value set
in Parameter 4 (T1 Top).
4. When the call for heat ends while target
temperature is "boosted," the target temperature
FIGURE 3 - PARAMETER 11 (AUTOMATIC SUPPLY TEMPERATURE BOOSTER OPERATION)
Temperature Boost Operation (Typical): In this example, the boiler is operating in outdoor reset mode with a calculated setpoint tem-
perature of 130°F. The call for heat has lasted more than 10 minutes (value of Parameter 11) and supply temperature boost has occured.
drops about 2° F for each minute the thermostat
is open.
5. Range: 1-30 minutes
6. Factory Default: 30 minutes.
7. Deactivate automatic temperature boost by
setting to "0."
MAXIMUM FAN SPEED
!
Fan speed must be set within the limits supplied
by the factory (See the "Default Parameters
Table" in Section II). Setting limits above or
below these factory defaults would increase or
decrease boiler firing rate beyond the acceptable
limit, resulting in potential for severe personal
injury, death, or substantial property damage.
• Parameters 13 and 15 can be set to limit the
maximum boiler firing rate. Boiler firing rate is
proportional to the fan speed, so reducing the
maximum fan speed reduces maximum input.
• Reducing maximum fan speed will be helpful for
systems on which the boiler is oversized for either
space heating or DHW, or both.
8
!
WARNING