Installation / Operation Instruction Manual

02/04/2021 28 BI810
Troubleshooting
Power Source
Electric element supply – the boiler vessel elements are fed from the main unit inside terminal block.
Depending upon model number and configuration this may require 480, 208, or 240 3-phase. See
Specification Table for specific installation requirement. This boiler is designed and wired for a Delta
electric element load arrangement. However, it can be serviced from a Y (no neutral current or hookup)
depending upon the utility transformer and the disconnect/wiring within the facility.
 If it is a true Delta service, a specific fault detector may be required.
24-volt control source, no PWR ON LED – verify 120 control power and control box upper left CB.
Verify 24-volt transformer, verify fuse, etc.
 If 24VAC is measured at the control module center left terminals and no PWR ON LED, control
board is inoperative.
 If there is no 24VAC at control module, troubleshoot transformer, fuse, 120 source, etc.
Component Information, Familiarization
Low water cutout (LWCO) – information on enclosure should be adequate.
On initial power the low water cut-off will be in the “closed” position.
 Sensor is on vessel, violet wire to LCO terminal.
 120 control power is at L1 and L2 tabs. The limit loop is from the CB to COM tab, NO tab, to
PCB J7 connector (K4 NC from HL-1 reset) to HL1 inside TB.
 Test switch is adjacent to the LWCO control. When pressed, the LWCO must be reset via the
reset button located on the lower right side of the control board.
Emergency stop switch field jumper – if the TB1-1 and 2 jumper is removed and a remote contact is put
in its place, when this contact is opened a fault display “Remote”. This is not a manual reset latching
circuit, the reset would need to be built into the remote connected device(s).
Manual reset hi-limit – this is the round, surface mount, limit installed on the vessel top plate. The TB1-
2 (L1) 120 passes through this limit (red and black wire) loop back to TB1-3 jumper. Internally at TB1-3
this 120 supplies all of the Sequencer pilot relay “COM” contacts (sequencer J1-10 and J2-8). When the
boiler top plate surface mount limit trips, the L1 120 switches from the black to the brown wire and via
TB1-5 provides an HL-1 monitor input to the Temp Sensing and Alarm module. This module has a
latching circuit (K4, two wire blk/yel loop, LWCO-5 to TB1-1) and the power for the Sequencer remains
interrupted until HL pushbutton reset.
Automatic reset hi-limit – screwed into the vessel top plate is a probe thermostat which has normally
closed contacts in series with 24VAC Sequencer 24V J3-8 (feeding into J3-5). Thus the automatic reset
removes all control power from the Sequencer. Also there is an HL-2 monitor wire fed to the control
module which activates an alarm.
Bad sensor– the OLED display indicates which sensor is faulty. In this instance, “faulty” means not
connected, shorted cable, or for some reason there is no digital bit pattern on the black wire. It does not
mean it’s an incorrect value, there is simply no data transmitted.
 This alarm is for notification, it does not cause a safety total shutdown same as LWCO, high
temp, Bender, etc.