3 constant setpoint mode, 1 setting the setpoint, Benchmark 1.5ln low nox boiler – AERCO BMK 1.5 LN July 2011 User Manual
Page 54: Gf-120

CHAPTER 5: MODE OF OPERATION
Page
54 of 152 PR2: 05/09/12
Benchmark 1.5LN Low NOx Boiler
Operation and Maintenance Manual
OMM-0041_0D
GF-120
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 • Ph: 800-526-0288
NOTE
A design engineer typically provides design outdoor air
temperature and supply header temperature data.
4. Once the design outdoor air temperature is chosen, go across the chart to the desired
supply header temperature for the design temperature chosen in step 3.
5. Next, go up that column to the Reset Ratio row to find the corresponding reset ratio.
6. Access the Configuration Menu and scroll through it until the display shows Bldg Ref Temp.
(Building Reference Temperature).
7. Press the
CHANGE key. The display will begin to flash.
8. Use the
▲ and ▼ arrow keys to select the desired Building Reference Temperature.
9. Press
ENTER to save any changes.
10. Next, scroll through the Configuration Menu until the display shows Reset Ratio.
11. Press the
CHANGE key. The display will begin to flash.
12. Use the
▲ and ▼ arrow keys to select the Reset Ratio determined in step 5.
13. Press
ENTER to save the change.
Refer to paragraph 3.3 for detailed instructions on menu changing.
5.3 CONSTANT SETPOINT MODE
The Constant Setpoint mode is used when a fixed header temperature is desired. Common
uses of this mode of operation include water source heat pump loops, and indirect heat
exchangers for potable hot water systems or processes.
No external sensors are required to operate in this mode. While it is necessary to set the
desired setpoint temperature, it is not necessary to change any other temperature-related
functions. The unit is factory preset with settings that work well in most applications. Prior to
changing any temperature-related parameters, other than the setpoint, it is suggested that an
AERCO representative be contacted. For descriptions of temperature-related functions and their
factory defaults, see Appendices A and E.
Setting the Setpoint
5.3.1
The setpoint temperature of the unit is adjustable from 40°F to 240°F. To set the unit for
operation in the Constant Setpoint Mode, the following menu settings must be made in the
Configuration Menu:
MENU OPTION
SETTING
Boiler Mode
Constant Setpoint
Internal Setpt
Select desired setpoint
using ▲ and ▼ arrow
keys (40°F to 240°F)
Refer to paragraph 3.3 for detailed instructions on changing menu options.