AERCO BMK 6000 Dual Fuel - Manual (Page 50)

Benchmark 6000 DF Installation, Operation & Maintenance Manual
CHAPTER 3 – OPERATION
Page 50 of 219 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 OMM-0096_0B
03/21/2014
Ph.: 800-526-0288
GF-141
Menu Item Display
Available Choices or Limits
Default
Minimum Maximum
Err Threshold 1 9 5
SSD Temp Format Degrees Points Degrees
BST Upld Timer 0 9999 sec 0
3.10 START SEQUENCE
When the Benchmark DF unit is set to natural gas, it checks only the natural gas side, and when
it is set to propane, it checks the propane side.
When the Control Box ON/OFF switch is set to the ON position, it checks all pre-purge safety
switches to ensure they are closed. These switches include:
• Downstream Safety Shut-Off Valve (SSOV) Proof of Closure (POC) switch
• Low Water Level switch
• High Water Temperature switch
• High Gas Pressure switch
• Low Gas Pressure switch
• Blower Proof switch
• Blocked Inlet switch
If all of the above switches are closed, the READY light above the ON/OFF switch will light and
the unit will be in the Standby mode.
When there is a demand for heat, the following events will occur:
NOTE
If any of the Pre-Purge safety device switches are open, the appropriate
fault message will be displayed. Also, if the required conditions are not
observed at any point during the start sequence, appropriate messages will
be displayed and the unit will go into fault mode.
1. The DEMAND LED status indicator will light.
2. The unit checks to ensure that the Proof of Closure (POC) switch in the downstream Safety
Shut-Off Valve (SSOV) is closed. See Figure 3-3 for the downstream SSOV location.