2 troubleshooting – Reznor LDAP Unit Installation Manual User Manual

Page 41

Form I-LDAP, P/N 207733R6, Page 41

The integrated circuit board monitors the operation of the heater and includes

two LED signal lights that indicate normal operation and various abnormal con-

ditions. If the heater fails to operate properly, check this signal to determine the

cause and/or to eliminate certain causes. See operating sequence in Para-

graph 8.

Do not attempt to repair the DSI integrated control module; the only field

replaceable component is the fuse.

Check the Lights on

the DSI Integrated

Control Module

(Circuit Board)

IMPORTANT: When

using a multimeter to

troubleshoot the 24 volt

circuit, place the meter’s

test leads into the 5 or 9

pin connectors located

on the ignition control.

Do not remove connec-

tors or terminals from the

electrical components.

Doing so can result in

misinterpreted readings

due to the ignition control

board’s fault mode moni-

toring circuits.

10.2 Troubleshooting

DSI Integrated Control

Module (Circuit Board)

Trial Troubleshooting

Flowchart

Control Status - GREEN LED Codes

Flame Status - YELLOW LED

Steady On Normal Operation - No call for heat. Steady On Flame is sensed.

Fast

Flash

Normal Operation - Call for heat.

Slow

Flash

Weak flame (current

below 1.0 microamps

±50%)

1 Flash System Lockout (failed to detect or

sustain flame)

2 Flash

Main combustion air pressure switch

or heat section pressure switch does

not close with 30 seconds of venter

being energized.

Fast

Flash

Undesired flame

(valve open and no

call for heat).

3 Flash Limit or high limit switch open.

4 Flash

Main combustion air pressure switch

or heat section pressure switch is

closed before venter is energized.

Steady

Off

Blown fuse; No power; or Defective

board

Trial for Ignition

Call for Heat

Is there a

spark across gap at

ignitor?

Does gas

ignite?

Is there minimum

flame current at the

flame sensor?

Is there

minimum flame current

at the control

module?

Replace control

module.

Check connections to flame

sensor and/or moisture in the

burner assembly.

Is the flame

sensor corroded?

Clean flame

sensor.

Is the sensor

located in flame

correctly?

Replace flame

sesnsor.

Reposition

flame sensor.

Is gas

flowing?

Is the ignitor

position correct in the

gas flow?

Check gas pressure

and supply voltage.

If either are low,

correct and repeat

startup.

Reposition

spark ignitor.

Is there

24VAC at the gas

valve?

Is there 24VAC

from gas valve output on

control module to

chassis?

Check wiring and

connections to

gas valve.

Replace

ignition

control

module.

Replace gas

valve.

Is there

spark voltage at

control?

Check high

voltage wire

continuity.

Is there 24V P1-2

to power control?

Replace

control

module.

Check wiring

and/or 24VAC

transformer output.

YES