Velocity Raptor RPTR155, Installation And Operating Instructions Manual

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XII. Operation
IMPORTANT
This boiler is equipped with a feature that saves energy by reducing the boiler water temperature
as the heating load decreases. This feature is equipped with an override which is provided
primarily to permit the use of an external energy management system that serves the same function.
THIS OVERRIDE MUST NOT BE USED UNLESS AT LEAST ONE OF THE FOLLOWING
CONDITIONS IS TRUE:
• An external energy management system is installed that reduces the boiler water
temperature as the heating load decreases.
• This boiler is not used for any space heating.
• This boiler is part of a modular or multiple boiler system having a total input of
300,000 BTU/hr or greater.
• This boiler is equipped with a tankless coil.
A. Overview
1. B1020 Controller
The B1020 Controller (Control) contains features
and capabilities which help improve heating system
operation, and efficiency. By including unique
capabilities, the Control can do more, with less field
wiring, and fewer aftermarket controls and components
– improving the operation of both new and replacement
boiler installations.
2. Advanced Touch Screen Display
Home Screen
Boiler status and setup selections are available from an
easy to use, LCD Touch Screen Display. In the event
of a fault condition the user is guided by “blinking”
touch buttons to Help screens that describe the problem.
Operation evaluation and problem-solving is enhanced
by historical capability including graphic trends,
lockout history records as well as boiler and circulator
cycle counts and run time hours.
3. Advanced Modulating Control
The Control modulates the boiler input by varying
the fan speed. As the fan speed increases, so does the
amount of fuel gas drawn into the blower. As a result,
a fairly constant air-fuel ratio is maintained across all
inputs. The Control determines the input needed by
looking at both current and recent differences between
the measured temperature and the setpoint temperature.
As the measured temperature approaches the setpoint
temperature, the fan will slow down and the input will
drop. The Control also utilizes boiler return water and
flue gas temperatures to adjust fan speed.
4. Built-in Safety Control
The Control includes safety controls designed to ensure
safe and reliable operation. In addition to flame safety
controls the Control includes supply water temperature,
differential water temperature, and stack temperature
safety limits and stepped modulation responses.
Boiler modulation is adjusted when required to help
avoid loss of boiler operation due to exceeding limits.
Additionally, the Control accepts the field installation
of optional auxiliary safety limits.
5. Outdoor Air Reset
When selected the modulation rate setpoint is
automatically adjusted based on outside air temperature,
time of day and length of demand (boost) settings.
Outdoor air “reset” setpoint saves fuel by adjusting
the water temperature of a heating boiler lower as the
outside air temperature increases.
6. Warm Weather Shutdown (WWSD)
Some boilers are used primarily for heating buildings,
and the boilers can be automatically shutdown when
the outdoor air temperature is warm. When outside air
temperature is above the WWSD setpoint, this function
will shut down the boiler, boiler and system pump.
7. Energy Management System (EMS) Interface
A factory configured RS485 Modbus interface is
available for Energy Management System (EMS)
monitoring when not used for Multiple Boiler
Sequencer Peer-To-Peer Network. Consult factory for
points list or if this interface must be used in addition
to the boiler Peer-to-Peer Network.
8. Circulator Control
The Control may be used to sequence the domestic
hot water, boiler and system circulators. Service rated
relay outputs are wired to a line voltage terminal block
for easy field connection. Simple parameter selections
allow all three pumps to respond properly to various
hydronic piping arrangements including either a boiler
or primary piped indirect water heater. Circulators may