Aerco Benchmark BMK 1000

Questions and Answers

K
Kevin WarrenNov 27, 2025
How to resolve an Airflow Fault during Run on my Aerco Boiler?
- S
  stephensjacquelineNov 27, 2025
  If the Aerco Boiler experiences an Airflow Fault during Run, several factors could be at play. The blower might have stopped running due to thermal or current overload; check the combustion blower for signs of excessive heat or high current draw. A blocked blower inlet or inlet ductwork is another possibility; inspect the inlet to the combustion blower, including any ductwork leading up to it, for signs of blockage. A blockage in the air filter or Blocked Inlet switch could also be the cause; remove the air filter and Blocked Inlet switch and inspect for signs of blockage, cleaning or replacing as necessary. A defective Blocked Inlet switch may also be the problem; verify that 24 VAC is present between each side of the switch and ground. If 24 VAC is not present at both sides, replace swit...
D
Darlene StoneAug 25, 2025
What causes a Delayed Interlock Open error on my Aerco Benchmark BMK 1000 Boiler?
- P
  Paul HendersonAug 25, 2025
  If the Aerco Boiler shows a Delayed Interlock Open error, the following could be the reasons: the Delayed Interlock Jumper might not be properly installed or is missing; check to ensure the jumper is properly installed across the delayed interlock terminals in the I/O Box. If there are 2 external wires on these terminals, check to see if an end switch for a proving device (such as a pump, louver, etc.) is tied these interlocks. Ensure that the device and/or its end switch is functional. A jumper may be temporarily installed to test the interlock.
W
William AdamsAug 29, 2025
How do I troubleshoot an Interlock Open error on my Aerco Boiler?
- A
  Amanda ColonAug 29, 2025
  If the Aerco Boiler displays an Interlock Open error, verify that a jumper is properly installed across the interlock terminals in the I/O box. If there are two external wires on these terminals check any Energy Management system to see if they have the units disabled (a jumper may be temporarily installed to see if the interlock circuit is functioning). Check that proving switch for any device hooked to the interlock circuit is closing and that the device is operational.
S
Steven WatsonAug 31, 2025
How do I fix a Stepper Motor Failure on my Aerco Benchmark BMK 1000?
- C
  Cheryl MorganAug 31, 2025
  If the Aerco Boiler reports a Stepper Motor Failure, consider these potential causes: the Air/Fuel Valve might be out of calibration, requiring you to perform the Stepper Feedback Calibration procedure in Section 6, section 6.2.1. Check that the Air/Fuel Valve is connected to the C-More Controller. Loose wiring connections to the stepper motor could be the issue; inspect for loose connections between the Air/Fuel Valve motor and the wiring harness. A defective Air/Fuel Valve stepper motor would need replacement. Check DS1 & DS2 LEDs on Power Supply Board. If they are not steady ON, replace Power Supply Board. Check “Heartbeat” LED DS1 and verify it is blinking ON & OFF every second. If not, replace IGST Board.
E
Eric AlexanderDec 1, 2025
Why does the High Water Temp Switch keep opening on my Aerco Benchmark BMK 1000 Boiler?
- K
  Kurt SavageDec 1, 2025
  If the High Water Temp Switch opens in the Aerco Boiler, several factors could be responsible: a faulty water temperature switch, which needs testing to ensure it trips at its set temperature. Incorrect PID settings can also cause this; check the settings and reset them to default values if they've been changed. A faulty shell temperature sensor might be the problem; measure the resistance of the Shell sensor and BTU sensor at a known water temperature using the resistance charts in Appendix C. Ensure that the unit is not in MANUAL mode; if it is, switch to AUTO mode. Also, verify that the unit setpoint is not greater than the Over Temperature switch setpoint; the temperature switch should be set higher than the unit’s setpoint. Finally, system flow rate changes occurring faster than the u...
J
Joseph ChavezSep 22, 2025
What to do if my Aerco Benchmark BMK 1000 Boiler reports a Recirc Pump Failure?
- K
  Kelly HicksSep 22, 2025
  If the Aerco Boiler indicates a Recirc Pump Failure, the internal recirculation pump has likely failed and needs replacement.
M
michaelhicksSep 17, 2025
What does it mean when my Aerco Benchmark BMK 1000 Boiler shows an SSOV Switch Open error?
- V
  Vickie MullenSep 18, 2025
  If the Aerco Boiler displays an SSOV Switch Open error, the actuator may not be allowing for full closure of the gas valve; observe the operation of the Safety Shut-Off Valve (SSOV) through the indicator on the Valve actuator and ensure that the valve is fully and not partially closing. The SSOV may be powered when it should not be. Remove the electrical cover from the SSOV and check switch continuity. If the switch does not show continuity with the gas valve closed, either adjust or replace the switch or actuator.
P
Paul CrawfordSep 18, 2025
How do I troubleshoot an Outdoor Temp Sensor Fault on my Aerco Boiler?
- B
  brendapettySep 18, 2025
  If the Aerco Boiler displays an Outdoor Temp Sensor Fault, inspect the Outdoor Temperature sensor for loose or broken wiring. Check resistance of sensor to determine if it is within specification. Ensure that the correct sensor is installed.
J
Jennifer CampbellSep 12, 2025
What causes a Line Voltage Out of Phase error on my Aerco Benchmark BMK 1000?
- D
  Diane ChurchSep 12, 2025
  If the Aerco Boiler displays a Line Voltage Out of Phase error, the following could be the reasons: the Line and Neutral might be switched in the AC Power Box, so check hot and neutral in AC Power Box to ensure they are not reversed. Incorrect power supply transformer wiring is another possibility; check transformer wiring, in AC Power Box, against the power box transformer wiring diagram to ensure it is wired correctly.
K
Kyle MooreSep 8, 2025
What causes a Remote Setpoint Signal Fault on my Aerco Boiler?
- B
  Brian MendozaSep 8, 2025
  If the Aerco Boiler displays a Remote Setpt Signal Fault, the potential causes include the remote setpoint signal not being present due to it not being installed, wrong polarity, a defective signal at the source, or broken or loose wiring. Check the I/O Box to ensure the signal is hooked up, and if not, hook it up. If installed, check the polarity. Measure the signal level and check the continuity of wiring between the source and the unit. If using a 4 to 20 mA signal, ensure the signal is isolated at the source. Check the DIP switch on the PMC board to ensure it is set correctly for the type of signal being sent. Check control signal type set in item 6 of the Configuration menu.

Summary

SECTION 1: SAFETY PRECAUTIONS

1.1 WARNINGS & CAUTIONS

General warnings and cautions for installers and operators.

1.2 EMERGENCY SHUTDOWN

Procedure for emergency shutdown if overheating occurs.

1.4 IMPORTANT - FOR MASSACHUSETTS INSTALLATIONS

Specific installation requirements for Massachusetts, including CO detectors.

SECTION 2: OPERATION

2.2 C-MORE CONTROLLER DESCRIPTION

Description of the C-More Controller's controls, indicators, and displays.

2.3 C-MORE CONTROLLER MENUS

Explanation of the C-More Controller's menu structure and navigation.

2.4 OPERATING Menu

Details of the Operating menu parameters for the unit.

2.5 SETUP Menu

Setup menu for password, date, time, and temperature units.

2.6 CONFIGURATION Menu

2.8 COMBUSTION CAL Menu

Combustion calibration menu for optimizing blower speed and efficiency.

2.10 CALIBRATION MENU

SECTION 3: MODES OF OPERATION

3.2 INDOOR;OUTDOOR RESET MODE

3.3 CONSTANT SETPOINT MODE

3.4 REMOTE SETPOINT MODES

3.5 DIRECT DRIVE MODES

SECTION 4: MAINTENANCE

4.1 MAINTENANCE SCHEDULE

Routine maintenance procedures and schedules for efficiency and reliability.

4.2 IGNITER-INJECTOR

4.3 FLAME DETECTOR

4.4 O2 SENSOR

4.5 SAFETY DEVICE TESTING

Systematic tests for operating and safety devices as per code requirements.

4.6 BURNER INSPECTION

4.9 WATER CUTOFF (LWCO) CAPACITOR INTEGRITY TEST

SECTION 5: TROUBLESHOOTING GUIDE

5.2 ADDITIONAL FAULTS WITHOUT SPECIFIC FAULT MESSAGES

APPENDIX A: BOILER MENU DESCRIPTIONS

TABLE A-1: OPERATING MENU ITEM DESCRIPTIONS

Descriptions of menu options within the Operating menu.

TABLE A-2: SETUP MENU ITEM DESCRIPTIONS

Descriptions of menu options within the Setup menu.

TABLE A-3: CONFIGURATION MENU ITEM DESCRIPTIONS

Descriptions of menu options within the Configuration menu.

TABLE A-4: TUNING MENU ITEM DESCRIPTIONS

TABLE A-5: COMBUSTION CALIBRATION MENU ITEM DESCRIPTIONS

Descriptions of menu options within the Combustion Calibration menu.

TABLE A-6: CALIBRATION MENU ITEM DESCRIPTIONS

Descriptions of menu options within the Calibration menu.

APPENDIX B: STARTUP, STATUS, & FAULT MESSAGES

TABLE B-1: Startup and Status Messages

List and descriptions of startup and status messages displayed.

TABLE B-2: Fault Messages

List and descriptions of fault messages displayed by the boiler.

APPENDIX D: RECOMMENDED PERIODIC TESTING

Recommended Periodic Testing

Table outlining recommended testing items, frequency, and action by whom.

APPENDIX F: BENCHMARK 750;1000 PART LIST

Benchmark 750 and Benchmark 1000 Part List

List of parts for Benchmark 750 and 1000 models.

APPENDIX G: BENCHMARK 1500;2000 PART LIST

Benchmark 1500;1500 DF & Benchmark 2000;2000 DF Part List

List of parts for Benchmark 1500/2000 models, including DF.

APPENDIX H: BENCHMARK 2500;3000 PART LIST

Benchmark 2500;2500 DF & Benchmark 3000;3000 DF Part List

List of parts for Benchmark 2500/3000 models, including DF.

APPENDIX K: RECOMMENDED SPARES

TABLE K-1: Recommended Emergency Spare Parts

List of recommended spare parts for emergency situations.

TABLE K-2: Recommended Spare Parts For Maintenance