Dunkirk Q90-200 Series II - Manual (Page 40)

40
Initial Service Checks
1.
Before Troubleshooting:
A. Verify circuit breaker is on or fuse is OK at electrical
panel.
B. Verify service switch is ON.
C. Verify Gas is ON at:
• Gas meter
• Appropriate manual shutoff valves
• Gas control valve
D. Verify thermostat is calling for heat.
E. Verify wire connections at integrated boiler control
(IBC) and originating control are securely plugged
in or connected.
F. Check hoses are securely connected and are not
plugged or damaged.
2.
Troubleshooting Tools:
A. Voltmeter to verify 120 VAC and 24 VAC
B. Continuity Tester
C. Inclined Manometer or Pressure Gauge with 0-2.0”
range (0.01” scale) for measuring suction pressures
at pressure switch.
D. U-Tube Manometer or Differential Pressure Gauge
with 0-14” range (0.1” scale) for measuring inlet
and manifold gas pressures.
3.
System Status:
A. Consult “System Status” on page 40.
B. See Figure 19, Page 26, for location of boiler
Diagnostic Indicator Lamps.
15 - TROUBLESHOOTING
WARNING
Fire, explosion or shock hazard may cause death or
serious injury. Do not attempt to modify physical or
electrical characteristics of this boiler in any way.
!
• In reset from lockout condition, all electrical meter
readings at gas control valve (24 vac) must be taken
within trial for ignition period.
• If any component dose not function properly, make
sure it is correctly installed and wired before replacing.
• Static electricity discharge can damage integrated
boiler control (IBC). Touch metal surface to discharge
static electricity before touching IBC.
• IBC cannot be repaired. If it malfunctions it must be
replaced.
• Only trained, experienced service technicians should
service IBC systems. Follow troubleshooting to check
out system and sequence of operation for normal light
off sequence.
• Defective control is least likely cause of malfunction.
If you suspect unit has defective control, read through
troubleshooting chart before replacing it.
• It is unlikely two consecutive controls are defective. If
this seems to be the case chances are the controls are
not the cause but rather malfunction is due to some
other problem such as electrical short burning out
transformer.