8 interlock tests, 1 remote interlock, 2 delayed interlock – AERCO BMK 1.5 LN Dual Fuel Feb 2013 User Manual

Page 72: 9 flame fault tests, Benchmark 1.5ln dual-fuel low nox boiler, Gf-121

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CHAPTER 6: SAFETY DEVICE TESTING

Page

72 of 162 PR2: 05/09/12

Benchmark 1.5LN Dual-Fuel Low NOx Boiler

Operation and Maintenance Manual

OMM-0041_0C

GF-121

AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 • Ph: 800-526-0288

6.8 INTERLOCK TESTS

The unit is equipped with two interlock circuits called the Remote Interlock and Delayed

Interlock. Terminal connections for these circuits are located in the I/O Box (Figure 2-9) and are

labeled REMOTE INTL’K IN and DELAYED INTL’K IN. These circuits can shut down the unit in

the event that an interlock is opened. These interlocks are shipped from the factory jumpered

(closed). However, each of these interlocks may be utilized in the field as a remote stop and

start, an emergency cut-off, or to prove that a device such as a pump, gas booster, or louver is

operational.

REMOTE INTERLOCK

6.8.1

1. Remove the cover from the I/O Box and locate the REMOTE INTL’K IN terminals.
2. Start the unit in the Manual Mode and set the valve position between 25% and 30%.
3. If there is a jumper across the REMOTE INTL’K IN terminals, remove one side of the

jumper. If the interlock is being controlled by an external device, either open the interlock

via the external device or disconnect one of the wires leading to the external device.

4. The unit should shut down and display INTERLOCK OPEN.
5. Once the interlock connection is reconnected, the INTERLOCK OPEN message should

automatically clear and the unit should restart.

DELAYED INTERLOCK

6.8.2

1. Remove the cover from the I/O Box and locate the DELAYED INTL’K IN terminals.
2. Start the unit in the Manual Mode at a valve position between 25% and 30%.
3. If there is a jumper across the DELAYED INTL’K IN terminals, remove one side of the

jumper. If the interlock is connected to a proving switch of an external device, disconnect

one of the wires leading to the proving switch.

4. The unit should shut down and display a DELAYED INTERLOCK OPEN fault message.

The

FAULT LED should be flashing.

5. Reconnect the wire or jumper removed in step 3 to restore the interlock.
6. Press the

CLEAR button to reset the fault

7. The unit should start.

6.9 FLAME FAULT TESTS

Flame faults can occur during ignition or while the unit is already running. To simulate each of

these fault conditions, proceed as follows:

1. Set the

ON/OFF switch to the OFF position.

2. Place the unit in the Manual Mode and set the valve position between 25% and 30%.
3. Close the Manual Shut-off Valve located between the Safety Shut-Off Valve (SSOV) and

the Air/Fuel Valve (see Figure 6-3).

4. Set the

ON/OFF switch to the ON position to start the unit.

5. The unit should shut down after reaching the Ignition cycle and display FLAME LOSS

DURING IGN.

6. Open the valve previously closed in step 3 and press the

CLEAR button.

7. Restart the unit and allow it to prove flame.

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