Watts AERCO Benchmark OMM-0121 User manual

Operation and Maintenance Manual
Other documents for this product include:
OMM-0121, GF-205 Installation & Startup Manual
TAG-0019, GF-2070 Boiler Application Guide
TAG-0022, GF-2050 Vent-Combustion Air Guide
TAG-0047, GF-2030 Benchmark Gas Guide
TAG-0048, GF-2060 Benchmark Power Guide
Applies to serial number:
G-19-0001 and above
Disclaimer
The information contained in this manual is subject to change without notice
from AERCO International, Inc. AERCO makes no warranty of any kind with
respect to this material, including, but not limited to, implied warranties of
merchantability and fitness for a particular application. AERCO International is
not liable for errors appearing in this manual, not for incidental or consequential
damages occurring in connection with the furnishing, performance, or use of
these materials
OMM-0122_D• GF-206 • 5/9/2019
Benchmark®Boilers
Natural Gas, Propane Gas and Dual Fuel
Fired Modulating & Condensing Boilers
Models 750 through 3000

Benchmark 750-3000 Boiler Operation & Maintenance Manual
CONTENTS
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TABLE OF CONTENTS
FOREWORD ......................................................................................................5
SECTION 1: SAFETY PRECAUTIONS ...................................................................9
1.1 WARNINGS & CAUTIONS .....................................................................................................................9
1.2 EMERGENCY SHUTDOWN.................................................................................................................10
1.3 PROLONGED SHUTDOWN.................................................................................................................10
1.4 IMPORTANT – FOR MASSACHUSETTS INSTALLATIONS...............................................................11
SECTION 2: OPERATION .................................................................................13
2.1 INTRODUCTION...................................................................................................................................13
2.2 C-MORE CONTROLLER DESCRIPTION............................................................................................14
2.3 C-MORE CONTROLLER MENUS........................................................................................................17
2.3.1 Menu Navigation and Processing Procedure..................................................................................................17
2.4 OPERATING MENU .............................................................................................................................19
2.5 SETUP MENU.......................................................................................................................................20
2.6 CONFIGURATION MENU ....................................................................................................................21
2.7 TUNING MENU.....................................................................................................................................23
2.8 COMBUSTION CAL MENU..................................................................................................................23
2.8.1 BMK 750/1000 COMBUSTION CAL Menu.......................................................................................................23
2.8.2 BMK 1500/2000 COMBUSTION CAL Menus ...................................................................................................24
2.8.3 BMK 2500/3000 COMBUSTION CAL Menus ...................................................................................................25
2.9 BST (BOILER SEQUENCING TECHNOLOGY) MENU .......................................................................26
2.10 CALIBRATION MENU.........................................................................................................................29
SECTION 3: MODES OF OPERATION ...............................................................31
3.1 INTRODUCTION...................................................................................................................................31
3.2 INDOOR/OUTDOOR RESET MODE ...................................................................................................31
3.2.1 Reset Ratio......................................................................................................................................................31
3.2.2 Building Reference Temperature....................................................................................................................31
3.2.3 Outdoor Air Temperature Sensor Installation ................................................................................................31
3.2.4 Indoor/Outdoor Startup .................................................................................................................................32
3.3 CONSTANT SETPOINT MODE ...........................................................................................................32
3.3.1 Setting the Setpoint ........................................................................................................................................33
3.4 REMOTE SETPOINT MODES .............................................................................................................33
3.4.1 Remote Setpoint Field Wiring.........................................................................................................................34
3.4.2 Remote Setpoint Startup ................................................................................................................................34
3.5 DIRECT DRIVE MODES.......................................................................................................................34
3.5.1 Direct Drive Field Wiring.................................................................................................................................35
3.5.2 Direct Drive Startup ........................................................................................................................................35
3.6 AERCO CONTROL SYSTEM (ACS)....................................................................................................36
3.6.1 ACS External Field Wiring................................................................................................................................36
3.6.2 ACS Setup and Startup....................................................................................................................................36
3.7 COMBINATION CONTROL SYSTEM (CCS).......................................................................................37
3.7.1 Combination Control System Field Wiring......................................................................................................38
3.7.2 Combination Control System Setup and Startup............................................................................................38
SECTION 4: MAINTENANCE ............................................................................39
4.1 MAINTENANCE SCHEDULE ...............................................................................................................39
4.2 IGNITER-INJECTOR ............................................................................................................................40

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4.3 FLAME DETECTOR .............................................................................................................................45
4.4 O2SENSOR..........................................................................................................................................45
4.5 SAFETY DEVICE TESTING.................................................................................................................46
4.6 BURNER INSPECTION........................................................................................................................46
4.6.1 BMK 750/1000 BURNER INSPECTION .............................................................................................................47
4.6.2 BMK 1500 – 3000 BURNER INSPECTION.........................................................................................................49
4.7 CONDENSATE DRAIN TRAP ..............................................................................................................53
4.8 AIR FILTER CLEANING AND REPLACEMENT ..................................................................................54
4.9 WATER CUTOFF (LWCO) CAPACITOR INTEGRITY TEST...............................................................55
4.9.1 Low Water Cutoff (LWCO) - Capacitor Electrical Short Test ...........................................................................56
4.9.2 Low Water Cutoff (LWCO) - Standard C-More Test ........................................................................................57
4.10 SHUTTING BOILER DOWN FOR EXTENDED PERIOD...................................................................57
4.11 PLACING THE BOILER BACK IN SERVICE AFTER A PROLONGED SHUTDOWN.......................58
4.12 SPARK MONITOR (AC CURRENT TRANSDUCER).........................................................................58
SECTION 5: TROUBLESHOOTING GUIDE .........................................................59
5.1 INTRODUCTION...................................................................................................................................59
5.2 ADDITIONAL FAULTS WITHOUT SPECIFIC FAULT MESSAGES ....................................................71
APPENDIX A: BOILER MENU ITEM DESCRIPTIONS .............................................73
TABLE A-1: OPERATING MENU ITEM DESCRIPTIONS .........................................................................73
TABLE A-2: SETUP MENU ITEM DESCRIPTIONS...................................................................................75
TABLE A-3: CONFIGURATION MENU ITEM DESCRIPTIONS ................................................................76
TABLE A-4: TUNING MENU ITEM DESCRIPTIONS.................................................................................79
TABLE A-5: COMBUSTION CALIBRATION MENU ITEM DESCRIPTIONS.............................................80
TABLE A-6: CALIBRATION MENU ITEM DESCRIPTIONS.......................................................................81
APPENDIX B: STARTUP, STATUS, & FAULT MESSAGES......................................85
TABLE B-1: STARTUP AND STATUS MESSAGES..................................................................................85
TABLE B-2: FAULT MESSAGES ...............................................................................................................86
APPENDIX C: SENSOR RESISTANCE/VOLTAGE CHART........................................89
APPENDIX D: RECOMMENDED PERIODIC TESTING ............................................91
APPENDIX E: INDOOR/OUTDOOR RESET RATIO CHARTS ..................................93
APPENDIX F: BENCHMARK 750/1000 PART LIST ...............................................97
APPENDIX G: BENCHMARK 1500/2000 PART LIST ...........................................107
APPENDIX H: BENCHMARK 2500/3000 PART LIST ...........................................123
APPENDIX I: WIRING DIAGRAMS ...................................................................145
APPENDIX J: C-MORE CONTROLLER VIEWS ....................................................161
APPENDIX K: RECOMMENDED SPARES ...........................................................163

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FOREWORD
The AERCO Benchmark (BMK) 750, 1000, 1500, 2000, 2500, and 3000 natural gas and
propane fueled boilers are modulating and condensing units. They represent a true industry
advance that meets the needs of today's energy and environmental concerns. Designed for
application in any closed loop hydronic system, the Benchmark's modulating capability relates
energy input directly to fluctuating system loads. These BMK models provide extremely high
efficiency operation and are ideally suited for modern low temperature, as well as, conventional
heating systems.
The Benchmark models operate within the following input and output ranges:
IMPORTANT!
Unless otherwise specified, all measurements apply to both natural gas and propane models.
Benchmark Boiler Intake and Output Ranges
MODEL
INPUT RANGE (BTU/HR.) OUTPUT RANGE (BTU/HR.)
MINIMUM MAXIMUM MINIMUM MAXIMUM
BMK 750 50,000 (14.6 kW) 750,000 (220 kW) 47,750 (14 kW) 716,250 (210 kW)
BMK 1000 50,000 (14.6 kW) 1,000,000 (293 kW) 48,300 (14.15 kW) 968,000 (284 kW)
BMK 1500 75,000 (22 kW) 1,500,000 (440 kW) 64,500 (18.9 kW) 1,395,000 (409 kW)
BMK 2000 100,000 (29.3 kW) 2,000,000 (586 kW) 86,000 (25.2 kW) 1,860,000 (545 kW)
BMK 2500 167,000 (48.9 kW) 2,500,000 (732 kW) 144,000 (42.2 kW) 2,395,000 (702 kW)
BMK 3000 200,000 (58.6 kW) 3,000,000 (879 kW) 174,000 (51.0 kW) 2,874,000 (842 kW)
The output of the boiler is a function of the unit’s firing rate (valve position) and return water
temperature.
When installed and operated in accordance with this Instruction Manual, these boilers comply
with the NOxemission standards outlined in: South Coast Air Quality Management District
(SCAQMD), Rule 1146.2. In addition, the BMK 750 & 1000 comply with the Bay Area Air
Quality Management District regulation 9, Rule 7.
Whether used in singular or modular arrangements, the BMK boilers offer the maximum venting
flexibility with minimum installation space requirements. These boilers are Category II and IV,
positive pressure appliances. Single and/or multiple breeched units are capable of operation in
the following vent configurations:
•Room Combustion Air:
oVertical Discharge
oHorizontal Discharge
•Ducted Combustion Air:
oVertical Discharge
oHorizontal Discharge
These boilers are capable of being vented utilizing Polypropylene and AL29-4C vent systems.
The Benchmark's advanced electronics are available in several selectable modes of operation
offering the most efficient operating methods and energy management system integration.

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AERCO Technical Terminology Meanings
TERMINOLOGY MEANING
A (Amp)
Ampere
ACS AERCO Control System, AERCO’s boiler management systems
ADDR Address
AGND Analog Ground
ALRM Alarm
ANSI American National Standards Institute,
ASME American Society of Mechanical Engineers
AUX Auxiliary
BAS Building Automation System, often used interchangeably with EMS
(see below)
Baud Rate
Symbol rate, or simply the number of distinct symbol changes
(signaling events) transmitted per second. It is not equal to bits per
second, unless each symbol is 1 bit long.
BMK (Benchmark) AERCO’s Benchmark series boilers
BMS or BMS II AERCO Boiler Management Systems
BLDG (Bldg) Building
BST AERCO on-board Boiler Sequencing Technology
BTU
British Thermal Unit. A unit of energy approximately equal to the
heat required to raise 1 pound (0.45 kg) of water 1°F (0.55 °C)
BTU/HR
BTUs per Hour
(1 BTU/hr = 0.29 W)
CCP
Combination Control Panel
CCS
Combination Control System
C-More Controller A
control system developed by AERCO and currently used in all
Benchmark, Innovation and KC1000 Series product lines.
CFH Cubic Feet per Hour (1 CFH = 0.028 m
3
/hr)
CO Carbon Monoxide
COMM (Comm) Communication
Cal. Calibration
CNTL Control
CPU Central Processing Unit
DBB
Double Block and Bleed, a gas trains containing 2 Safety Shutoff
Valves (SSOVs) and a solenoid operated vent valve.
DIP Dual In-Line Package, a type of switch
ECU Electronic Control Unit (O2 sensor)
EMS Energy Management System; often used interchangeably with BAS
FM Factory Mutual. Used to define boiler gas trains.
GF-xxxx Gas Fired (an AERCO document numbering system)
GND Ground

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AERCO Technical Terminology Meanings
TERMINOLOGY MEANING
HDR
Header
Hex Hexadecimal Number (0 – 9, A – F)
HP Horse Power
HX Heat Exchanger
Hz Hertz (Cycles Per Second)
I.D. Inside Diameter
IGN Ignition
IGST Board Ignition/Stepper Board, contained in the C-More Controller
INTLK (INTL’K) Interlock
I/O Input/Output
I/O Box Input/Output (I/O) Box currently used on Benchmark, Innovation and
KC1000 Series products
IP Internet Protocol
ISO International Organization for Standardization
Lbs. Pounds (1 lb = 0.45 kg)
LED Light Emitting Diode
LN Low Nitrogen Oxide
MA (mA) Milliampere (1 thousand
th
of an ampere)
MAX (Max) Maximum
MBH
1000 BTUs per Hour
MIN (Min) Minimum
Modbus® A serial, half-
duplex data transmission protocol developed by AEG
Modicon
NC (N.C.) Normally Closed
NO (N.O.) Normally Open
NOxNitrogen Oxide
NPT National Pipe Thread
O2Oxygen
O.D. Outside Diameter
OMM & O&M Operation and Maintenance Manual
onAER AERCO’s on-line remote monitoring system
PCB Printed Circuit Board
PMC Board Primary Micro-Controller (PMC) board, contained in the C-More
P/N Part Number
POC
Proof of Closure
PPM
Parts per Million
PSI
Pounds per Square Inch (1 PSI = 6.89 kPa)
PTP
Point-to-Point (usually over RS232 networks)

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AERCO Technical Terminology Meanings
TERMINOLOGY MEANING
P&T
Pressure and Temperature
ProtoNode Hardware interface between BAS and a boiler or water heater
PVC Poly Vinyl Chloride, a common synthetic plastic
PWM Pulse Width Modulation
REF (Ref) Reference
RES. Resistive
RS232
(or EIA-232)
A standard for serial, full-
duplex (FDX) transmission of data based
on the RS232 Standard
RS422
(or EIA-422) A standard for serial, full-
duplex (FDX) transmission of data based
on the RS422 Standard
RS485
(or EIA-485)
A standard for serial, half-duplex (HDX) transmission of data based
on the RS485 Standard
RTN (Rtn) Return
SETPT (Setpt) Setpoint Temperature
SHLD (Shld) Shield
SPDT Single Pole Double Throw, a type of switch
SSOV Safety Shut Off Valve
TEMP (Temp) Temperature
Terminating Resistor A resistor placed at each end of a daisy-chain or multi-drop network
in order to prevent reflections that may cause invalid data in the
communication
Tip-N-Tell A device that indicates if a package was tipped during shipping
UL A business that tests and validates products
VAC Volts, Alternating Current
VDC Volts, Direct Current
VFD Vacuum Fluorescent Display, also Variable Frequency Drive
W Watt
W.C. Water Column, a unit of pressure (1 W.C. = 249 Pa)
µA Micro amp (1 million
th
of an ampere)

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SECTION 1: SAFETY PRECAUTIONS
1.1 WARNINGS & CAUTIONS
Installers and operating personnel MUST, at all times, observe all safety regulations. The
following warnings and cautions are general and must be given the same attention as specific
precautions included in these instructions. In addition to all the requirements included in this
AERCO Instruction Manual, the installation of units MUST conform with local building codes, or,
in the absence of local codes, ANSI Z223.1 (National Fuel Gas Code Publication No. NFPA-54)
for gas-fired boilers and ANSI/NFPASB for LP gas-fired boilers. Where applicable, the
equipment shall be installed in accordance with the current Installation Code for Gas Burning
Appliances and Equipment, CSA B149.1, and applicable Provincial regulations for the class;
which should be carefully followed in all cases. Authorities having jurisdiction should be
consulted before installations are made.
See section 1.4 for important information regarding installation of units within the
Commonwealth of Massachusetts.
IMPORTANT!
This Instruction Manual is an integral part of the product and must be maintained in legible
condition. It must be given to the user by the installer and kept in a safe place for future
reference.
WARNING!
•Do not use matches, candles, flames, or other sources of ignition to check for gas leaks.
•Fluids under pressure may cause injury to personnel or damage to equipment when
released. Be sure to shut off all incoming and outgoing water shutoff valves. Carefully
decrease all trapped pressures to zero before performing maintenance.
•Before attempting to perform any maintenance on the unit, shut off all gas and electrical
inputs to the unit.
•The exhaust vent pipe of the unit operates under a positive pressure and therefore must be
completely sealed to prevent leakage of combustion products into living spaces.
•Electrical voltages up to 120 VAC may be used in this equipment. Therefore the cover on
the unit’s power box (located behind the front panel door) must be installed at all times,
except during maintenance and servicing.
•A three-pole switch must be installed on the electrical supply line of the unit. The switch
must be installed in an easily accessible position to quickly and safely disconnect electrical
service. Do not affix switch to unit sheet metal enclosures.
CAUTION!
•Many soaps used for gas pipe leak testing are corrosive to metals. The piping must be
rinsed thoroughly with clean water after leak checks have been completed.
•DO NOT use this boiler if any part has been under water. Call a qualified service technician
to inspect and replace any part that has been under water.

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1.2 EMERGENCY SHUTDOWN
If overheating occurs or the gas supply fails to shut off, close the manual gas shutoff valve
(Figure 1-1) located external to the unit.
NOTE:
The Installer must identify and indicate the location of the emergency shutdown manual gas
valve to operating personnel.
Figure 1-1: Manual Gas Shutoff Valve
In addition, to ensure safety an emergency shutdown procedure that addresses the following
points should be designed and implement at the site:
•For automatically operated unattended boilers located in a boiler room, provide a manually
operated remote shutdown switch or circuit breaker located just inside or outside each boiler room
door. Design the system so activation of the emergency shutdown switch or circuit breaker will
immediately shut off the fuel supply to the unit(s).
•For automatically operated unattended boilers in a location other than a boiler room, provide a
manually operated remote shutdown switch or circuit breaker marked for easy identification at a
location readily accessible in the event of boiler mis-operation.
•Design the system so activation of the emergency shutdown switch or circuit breaker will
immediately shut off the fuel.
•For boilers monitored and/or operated from a continuously occupied control room, provide an
emergency shutdown switch in the control room that is hard-wired to immediately shut off the fuel
upon activation.
1.3 PROLONGED SHUTDOWN
If there is an emergency, turn off the electrical power supply to the boiler and close the manual
gas valve located upstream the unit. The installer must identify the emergency shut-off device.
If the boiler needs to be shut down for a prolonged period, follow the instructions in Section
4.10: Shutting Boiler Down For Extended Period of this manual.
After prolonged shutdown, it is recommended that the procedures in Section 4: Initial Startup
and Section 5: Safety Device Testing of the Benchmark 750-3000 Installation and Startup Guide
(OMM-0121, GF-205) be performed to verify that all system-operating parameters are correct.
VALVE
OPEN
VALVE
CLOSED

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1.4 IMPORTANT – FOR MASSACHUSETTS INSTALLATIONS
Requirements For Massachusetts Installations
Boiler Installations within the Commonwealth of Massachusetts must conform to the
following requirements:
•Boiler must be installed by a plumber or a gas fitter who is licensed within the
Commonwealth of Massachusetts.
•Prior to unit operation, the complete gas train and all connections must be leak
tested using a non-corrosive soap.
•The vent termination must be located a minimum of 4 feet above grade level. If
side-wall venting is used, the installation must conform to the following
requirements extracted from 248 CMR 5.08 (2):
(a) For
all side wall horizontally vented gas fueled equipment installed in every dwelling,
building or structure used in whole or in part for residential purposes, including those owned or
operated by the Commonwealth and where the side wall exhaust vent termination is less than
seven (7) feet above finished grade in the area of the venting, including but not limited to decks
and porches, the following requirements shall be satisfied:
1. INSTALLATION OF CARBON MONOXIDE DETECTORS:At the time of installation of the
side wall horizontal vented gas fueled equipment, the installing plumber or gasfitter shall
observe that a hard wired carbon monoxide detector with an alarm and battery back-up is
installed on the floor level where the gas equipment is to be installed. In addition, the
installing plumber or gasfitter shall observe that a battery operated or hard wired carbon
monoxide detector with an alarm is installed on each additional level of the dwelling,
building or structure served by the side wall horizontal vented gas fueled equipment. It shall
be the responsibility of the property owner to secure the services of qualified licensed
professionals for the installation of hard wired carbon monoxide detectors.
a. In the event that the side wall horizontally vented gas fueled equipment is installed in a
crawl space or an attic, the hard wired carbon monoxide detector with alarm and battery
back-up may be installed on the next adjacent floor level.
b. In the event that the requirements of this subdivision can not be met at the time of
completion of installation, the owner shall have a period of thirty (30) days to comply with
the above requirements; provided, however, that during said thirty (30) day
period, a
battery operated carbon monoxide detector with an alarm shall be installed.
2. APPROVED CARBON MONOXIDE DETECTORS:
Each carbon monoxide detector as
required in
accordance with the above provisions shall comply with NFPA 720 and be
ANSI/UL 2034 listed and IAS certified.
3. SIGNAGE:A metal or plastic identification plate shall be permanently mounted to the
exterior of the building at a minimum height of eight (8) feet above grade directly in line
with the exhaust vent terminal for the horizontally vented gas fueled heating appliance or
equipment. The sign shall read, in print size no less than one-half (1/2) inch in size, "GAS
VENT DIRECTLY BELOW. KEEP CLEAR OF ALL OBSTRUCTIONS". (Continued)

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Requirements For Massachusetts Installations
4. INSPECTION:The state or local gas inspector of the side wall horizontally vented gas
fueled equipment shall not approve the installation unless, upon inspection, the inspector
observes carbon monoxide detectors and signage installed in accordance with the
provisions of 248 CMR 5.08(2)(a)1 through 4.
(b) EXEMPTIONS: The following equipment is exempt from 248 CMR 5.08(2)(a)1 through 4:
1. The equipment listed in Section 10 entitled "Equipment Not Required To Be Vented" in
the most current edition of NFPA 54 as adopted by the Board; and
2. Product Approved side wall horizontally vented gas fueled equipment installed in a
room or structure separate from the dwelling, building or structure used in whole or in
part for residential purposes.
(c) MANUFACTURER REQUIREMENTS - GAS EQUIPMENT VENTING SYSTEM PROVIDED. When
the manufacturer of Product Approved side wall horizontally vented gas equipment provides a
venting system design or venting system components with the equipment, the instructions
provided by the manufacturer for installation of the equipment and the venting system shall
include:
1. Detailed instructions for the installation of the venting system design or the venting
system components; and
2. A complete parts list for the venting system design or venting system.
(d) MANUFACTURER REQUIREMENTS - GAS EQUIPMENT VENTING SYSTEM NOT PROVIDED.
When the manufacturer of a Product Approved side wall horizontally vented gas fueled
equipment does not provide the parts for venting the flue gases, but identifies "special venting
systems", the following requirements shall be satisfied by the manufacturer:
1. The referenced "special venting system" instructions shall be included with the appliance
or equipment installation instructions; and
2. The "special venting systems" shall be Product
Approved by the Board, and the
instructions for that system shall include a parts list and detailed installation instructions.
(e) A copy of all installation instructions for all Product Approved side wall horizontally vented
gas fueled equipment, all venting instructions, all parts lists for venting instructions, and/or all
venting design instructions shall remain with the appliance or equipment at the completion of
the installation.
……………….[End of Extracted Information From 248 CMR 5.08 (2)]…………………

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SECTION 2: OPERATION
2.1 INTRODUCTION
The information in this section provides a guide to the operation of the Benchmark Boiler using
the C-More Controller mounted on the front of the unit. It is imperative that the initial startup of
this unit be performed by factory trained personnel. Operation prior to initial startup by factory
trained personnel may void the equipment warranty. In addition, the following WARNINGS and
CAUTIONS must be observed at all times.
WARNING!
•ELECTRICAL VOLTAGES IN THIS SYSTEM INCLUDE 120 VAC (BMK 750 – 2000) and
208 or 460 VAC (BMK 2500/3000) and 24 volts AC. It must be serviced only by factory
certified service technicians.
•DO NOT ATTEMPT TO DRY FIRE THE UNIT. Starting the unit without a full water level
can seriously damage the unit and may result in injury to personnel or property damage.
This situation will void any warranty.
CAUTION!
All of the installation procedures in the Benchmark 750 – 3000 Installation and Startup Guide,
OMM-0121 (GF-205) must be completed before attempting to start the unit.

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2.2 C-MORE CONTROLLER DESCRIPTION
All Benchmark boilers utilize the C-More Controller shown in Figure 2-1. This panel contains all
of the controls, indicators and displays necessary to operate, adjust and troubleshoot the boiler.
These operating controls, indicators and displays are listed and described in Table 2-1.
Additional information on these items is provided in the individual operating procedures and
menu descriptions provided in this section.
Figure 2-1: C-More Controller Front View
1
12
11
10
9
8
7
5
4
3
6
2

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TABLE 2-1: Controls, Indicators, And Displays (ref. Figure 2-1)
ITEM CONTROL, INDICATOR
or DISPLAY FUNCTION
1
LED STATUS INDICATORS
Four Status LEDs indicate the current operating status as follows:
COMM = Lights when RS232 communication is occurring – see Item 4.
MANUAL = Lights when the valve position (fire rate) is being controlled using the front
panel keypad. This mode of operation is for service technician use only.
REMOTE = Lights when the unit is being controlled by an external signal from an Energy
Management System.
DEMAND = Lights when there is a demand for heat.
2 OUTLET
TEMPERATURE
Display
3–Digit, 7–
Segment LED display continuously displays the outlet
water temperature. The °F or °C LED next to the display lights to
indicate whether the displayed temperature is in degrees Fahrenheit
or degrees Celsius. The °F or °C blinks when operating in the
DEADBAND mode.
On a BST Manager, display flashes & shows header temperature.
3 VFD Display
Vacuum Fluorescent Display (VFD) consists of 2 lines each capable
of displaying up to 16 alphanumeric characters. The information
displayed includes:
•Startup Messages
•Fault Messages
•Operating Status Messages
•Menu Selection
•BST Messages
4 RS232 Port This port is used only by factory-
trained personnel to monitor
onAER
communications, in combination with the RS232 Adaptor
Cable (P/N 124675).
5 FAULT Indicator Red FAULT
LED indicator lights when a boiler alarm condition
occurs. An alarm message will appear in the VFD.
6 CLEAR Key Turns off the FAULT indicator and clears the alarm message if the
alarm is no longer valid. Lockout type alarms will be latched and
cannot be cleared by simply pressing this key. Troubleshooting
may be required to clear these types of alarms.
7 READY Indicator Lights when ON/OFF switch is set to ON and when all Pre-Purge
conditions have been satisfied.
8
ON/OFF switch Enables and disables boiler operation.
9
LOW WATER
LEVEL
TEST/RESET
switches
•Allows operator to test operation of the water level monitor.
•Pressing TEST
opens the water level probe circuit and
simulates a Low Water Level alarm.
•Pressing RESET resets the water level monitor circuit.
•Pressing the CLEAR key (item 6) resets the display.

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TABLE 2-1: Controls, Indicators, And Displays (ref. Figure 2-1)
ITEM CONTROL, INDICATOR
or DISPLAY FUNCTION
10
MENU KEYPAD
Six (6) keys which provide the following functions for the C-More Controller menus:
MENU Steps through the main menu categories shown in Figure 2-2. The menu
categories wrap around in the order shown.
BACK
Allows you to go back to the previous menu level without changing any
information. Continuously pressing this key will bring you back to the
default status display in the VFD. Also, this key allows you to go back to
the top of a main menu category.
▲
(UP)
Arrow
When in one of the main menu categories (Figure 2-2), pressing the ▲
arrow key will select the displayed menu category. If the CHANGE key was
pressed and the menu item is flashing, pressing the ▲
arrow key will
increment the selected setting.
▼
(DOWN)
Arrow
When in one of the main menu categories (Figure 2-2), pressing this key
will select the displayed menu category. If the CHANGE key was pressed
and the menu item is flashing, pressing the ▼ arrow key will decrement the
selected setting.
CHANGE
Permits a setting to be changed (edited). When the CHANGE
key is
pressed, the displayed menu item will begin to flash. Pressing the ▲or ▼
arrow key when the item is flashing will increment or decrement the
displayed setting.
ENTER
Saves the modified menu settings in memory. The display will stop
flashing.
11 AUTO/MAN switch
This switch toggles the boiler between the AUTOMATIC and
MANUAL modes of operation. When in the MANUAL (MAN) mode,
the front panel controls are enabled and the MANUAL status LED
lights. Manual operation is for service only.
When in the AUTOMATIC (AUTO) mode, the MANUAL status LED
will be off and the front panel controls disabled.
12 VALVE POSITION
Bargraph 20 segment red LED bargraph continuously shows the Air/Fuel
Valve position in 5% increments from 0 to 100%

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2.3 C-MORE CONTROLLER MENUS
The C-More Controller incorporates an extensive menu structure which permits the operator to
set up, and configure the unit. The menu structure consists of five major menu categories which
are applicable to this manual. These categories are shown in Figure 2-2. Each of the menus
shown, contain options which permit operating parameters to be viewed or changed. The
menus are protected by password levels to prevent unauthorized use.
Prior to entering the correct password, the options contained in the Operation, Setup,
Configuration and Tuning menu categories can be viewed. However, with the exception of
Internal Setpoint Temperature (Configuration menu), none of the viewable menu options can be
changed.
Once the valid level 1 password (159) is entered, the options listed in the Setup, Configuration
and Tuning menus can be viewed and changed, if desired. The Combustion Cal menu is
protected by the level 2 password (6817), which is used in initial startup (see Section 4: Initial
Startup of the Benchmark 750 – 3000 Installation and Startup Guide, OMM-0121 (GF-205)), to
perform combustion calibration prior to service use.
2.3.1 Menu Navigation and Processing Procedure
Accessing and initiating each menu and option is accomplished using the menu keys shown in
Figure 2-1. Therefore, it is imperative that you be thoroughly familiar with the following basic
steps before attempting to perform specific menu procedures:
Menu Navigation and Processing Procedure Instructions
1. The C-More Controller will normally be in the Operating menu and the VFD will display the
current unit status. Pressing the ▲ or ▼ arrow key will display the other available data
items in the Operating menu.
2. Press the MENU key. The display will show the Setup
menu, which is the next menu
category shown in Figure 2-2. This menu contains the Password option which must be
entered if other menu options will be changed.
3. Continue pressing the MENU key until the desired menu is displayed.
4. With the desired menu displayed, press the ▲ or ▼ arrow key. The first option
in the
selected menu will be displayed.
5.
Continue to press the ▲ or ▼ arrow key until the desired menu option is displayed.
Pressing the ▲ arrow key will display the available menu options in the Top-Down
sequence. Pressing the ▼ arrow key will display the options in the Bottom-Up sequence.
The menu options will wrap-around after the first or last available option is reached.
6. To change the value or setting of a displayed menu option, press the CHANGE key. The
displayed option will begin to flash. Press the ▲ or ▼ arrow key to scroll through the
available menu option choices for the option to be changed. The menu option choices do
not wrap around.
7. To select and store a changed menu item, press the ENTER key.

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* Only if BST is enabled. BST is described in detail in Section 6 of the Benchmark 750 – 3000
Installation and Startup Guide, OMM-0121 (GF-205).
Figure 2-2: Menu Structure
NOTE:
The following sections provide brief descriptions of the options contained in each menu.
Refer to Appendix A for detailed descriptions of each menu option. Refer to Appendix B
for a list and descriptions of startup, status and error messages.

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2.4 OPERATING Menu
The Operating menu displays a number of key operating parameters for the unit. All items in this
menu except O2 Monitor (item 15) are “Read-Only” and cannot be changed. This menu can be
accessed without entering a password.
A full description of each item appears in Appendix A-1.
TABLE 2-2: OPERATING Menu
MENU ITEM DISPLAY AVAILABLE CHOICES OR LIMIT Appears Only If
Enabled in:
Minimum
Maximum
1 Active Setpoint 40°F (4.4°C) 240°F (116°C)
2 Outlet Temp 30°F (-1.1°C) 240°F (116°C) Configuration Menu
3 Inlet Temp 30°F (-1.1°C) 240°F (116°C)
4 Air Temp -70°F (-56.7°C) 245°F (118°C)
5 Outdoor Temp -70°F (-56.7°C) 130°F (54.4°C) Configuration Menu
6 Valve Position In 0% 100%
7 Valve Position Out 0% 100% Configuration Menu
8 FFWD Temp
30°F (-1.1°C)
240°F (115.6°C)
9 Exhaust Temp Displays current exhaust temperature
10 Flame Strength 0% 100%
11 Min Flame Str Not Used
12 O2 Monitor Enable Disable O2 Monitor = Enabled
13 Oxygen Level 0% 21%
14 Ignition Time 0.00 10.00
15 SSOV Time to OPN 0.00 10.00
16 Spark Current 0 amps 2.5 amps
17 Run Cycles 0 999,999,999
18 Run Hours 0 999,999,999
19 Fault Log 0 19
An additional parameter associated with the Operating menu, (Min = 0, Max = 100) does not
appear in this menu, but can be displayed by pushing the Auto/Man button on the C-More
Controller’s front face.

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2.5 SETUP Menu
The Setup menu permits the operator to enter the unit password (159) which is required to
change the menu options. To prevent unauthorized use, the password will time-out after 1 hour.
Therefore, the correct password must be reentered when required. In addition to permitting
password entries, the Setup menu is also used to enter date and time, and units of temperature
measurements. A view-only software version display is also provided to indicate the current C-
More Controller software version.
A full description of each item appears in Appendix A-2.
TABLE 2-3: SETUP Menu
MENU ITEM DISPLAY AVAILABLE CHOICES OR LIMIT DEFAULT
Minimum Maximum
1 Password 0 9999 0
2
Language
English
English
3
Time
12:00 am
11:59 pm
12:00
4
Date 01/01/00 12/31/99 01/01/00
5
Unit of Temp
Fahrenheit or Celsius
Fahrenheit
6
Comm Address 0 127 0
7
Baud Rate
2400, 4800, 9600, 19.2K
9600
8 onAER Mode Ethernet or SD Card Ethernet
9 Min Upload Timer 0 9,999 Sec 0
10 Unit Alpha E, G, H, R, N or A A
11 Unit Year 0 99 0
12 Unit Serial # 0 9999 0
13 Software Ver 0.00 Ver 9.99 Current software
version