Benchmark 2500 - 3000 Boilers
CHAPTER 6 – SAFETY DEVICE TESTING
OMM-0094_0E
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
Page
77
of
204
GF-137
Ph.: 800-526-0288
03/20/2014
6.6 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 2-12) 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.
6.6.1 Remote Interlock Test
Remote Interlock Test
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.
6.6.2 Delayed Interlock Test
Delayed Interlock Test
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.