PeerlessBoilers PBC-40 - Outdoor Reset Operation

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I. OUTDOOR RESET OPERATION
All Series PBC™ boilers come with the default Central
Heat mode set to outdoor reset with room thermostat
(ODR). This feature uses the information from the
provided Outdoor Sensor to automatically adjust the
boiler setpoint based on the required heat load on the
building as the outdoor temperature changes. Figure 8.3
above visualizes the curve that is controlled by parameters
2019 through 2027.
1. The Boiler Design Temperature (2019) and Outdoor
Design Temperature (2020) control the maximum
setpoint and the temperature at which it will be
targeted.
2. The Boiler Mild Weather Temperature (2021) and
Outdoor Mild Weather Temperature (2022) control the
minimum setpoint and temperature at which it will be
targeted
3. The Minimum CH setpoint (2023) controls how low
the calculated setpoint can fall.
4. The maximum CH setpoint (2024) controls how high
the calculated setpoint can rise when boost is active.
5. The Mild Weather Shutdown Temperature (2025)
allow for control over what outdoor temperature the
boiler will begin ignoring CH demands.
6. The Boost Function Increment (2026) allows for control
over how aggressively the Boost function will increase
the calculated setpoint after the boost delay is met.
7. The Boost Function Delay allows for control over the
timeframe the CH demand must be present without
the call being satisfied before the Boost Function will
begin increasing the calculated setpoint.
Figure 8.3: Outdoor Reset Curve Logic
BOILER CONTROL: INTERNAL WIRING & OPERATION
Table 8.8: Outdoor Reset Parameters
Status
(2000)
Parameters
Parameter Function
Unit/Value
Default
Options
2019
Boiler Supply Design Temperature
–
Sets the reset curve design temperature that will be targeted when the outdoor temperature
is at the chosen outdoor design temperature.
–
For default: Boiler will target 190°F when the outdoor temperature is 23°F or lower.
°F 190
2020
Outdoor Design Temperature
–
Sets the Outdoor Temperature at which the boiler will target the Boiler Supply Design
Temperature.
–
For default: Boiler will target 190°F when the outdoor temperature is 23°F or lower.
°F 23
2021
Boiler Mild Weather Temperature
–
Sets the reset curve design temperature that will be targeted when the outdoor temperature
is at the Outdoor Mild Weather temperature.
–
For default: Boiler will target 104°F when the outdoor temperature is 68°F.
°F 104