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A. CONTROL OVERVIEW
The Series PBC™ boiler control is one of the primary
safety devices for the boiler. It controls:
• Ignition sequence
• Temperature Limits
• Circulators
• Gas Flow
• Setpoints
• Domestic Hot Water Valve
• Fan Speed
• LWCO (When optional LWCO probe is used)
B. AVAILABLE CENTRAL HEAT MODES
BOILER CONTROL: INTERNAL WIRING & OPERATION
Table 8.1: Series PBC™ Central Heat Modes
8. BOILER CONTROL: INTERNAL
WIRING & OPERATION
Central
Heating
Mode
Mode Description
Mode Operation
Restrictions
0
Fixed Setpoint
– Demand initiated by T/TT closure
– User chosen fixed setpoint
– Boiler targets CH setpoint and operates of Supply temperature
hysteresis when demand is present
Not for space heating
1
Outdoor reset with Thermostat
– Demand initiated by T/TT closure
– Setpoint is calculated based off of Outdoor temperature and CH
demand period to improve fuel usage and boiler efficiency.
– Setpoint Boost function for long CH demand periods.
– Boiler targets calculated CH setpoint and operates off of Supply
temperature hysteresis when demand is present
– When the Boost Function was active and CH demand is not present,
the CH setpoint decreases back to the calculated setpoint.
No restrictions
2
Outdoor reset with Permanent
Demand
– Demand initiated by control logic. Always present.
– Setpoint is calculated based off of Outdoor temperature to improve
fuel usage and boiler efficiency.
– Boiler targets calculated CH setpoint and operates off of Supply
temperature hysteresis.
– When CH demand is not present, calculated setpoint decreases
gradually.
No restrictions
3
Fixed Setpoint with Permanent
Demand
– Demand initiated by control logic. Always present.
– User chosen fixed setpoint
– Boiler maintains CH setpoint and operates of Supply temperature
hysteresis
Not for space heating
*While accessible via the Installer menu, CH Modes 4 and 5 are not functional with the Series PBC™ boiler.
Содержание PBC-34
Страница 1: ...PBC Gas Boilers PBC 34 PBC 40 PBC 52 Combination Installation Operation Maintenance Manual Series...
Страница 22: ...20 WATER PIPING AND CONTROLS Figure 4 6 Recommended Central Heat Piping...
Страница 23: ...21 Figure 4 7 Recommended Domestic Hot Water Piping WATER PIPING AND CONTROLS...
Страница 31: ...29 Figure 7 2 Wiring Schematic and Connection ELECTRICAL CONNECTIONS...
Страница 45: ...E LIGHTING OPERATING PROCEDURES 43 START UP PROCEDURE...
Страница 57: ...THIS PAGE INTENTIONALLY LEFT BLANK...
Страница 60: ...58 REPAIR PARTS Figure 13 2 PBC 34 Combustion Components...
Страница 62: ...60 REPAIR PARTS Figure 13 3 PBC 40 and PBC 52 Combustion Components...