Heatilator NBV30-IFT Owner’s Manual Operation And Maintenance page 21

IntelliFire Touch - (continued)
Symptom
Pilot sparks but does not light,
after 90 sec, 3 Red/1 Green
Lockout
Pilot lights but main burner
does not light. Pilot continues
to spark for 90 sec then goes
into 3 Red/1 Green Lockout.
Pilot lights and rectifies, but
main burner does not light.
Pilot and main do not light,
ECM goes into 5 Red/1 Green
Lockout.
Appliance lights and runs for a
few minutes then shuts down
and/or appliance cycle ON
and OFF with less than 90 sec
of ON time.
No power to appliance.
Heatilator • NBV30-IFT, NBV33-IFT, NBV36-IFT, NBV42-IFT Owner's Manual • 2624-981 Rev. C • 8/20
Possible Cause
No gas supply.
ECM has poor ground.
Gas valve defective.
No flame detected. Flame
rectification issue.
No flame detected or sense rod
contamination.
Main valve solenoid.
Power Vent (PV) Failure.
Shorted or loose connection in
flame detection circuit.
Poor flame rectification or
contaminated sense rod.
Logs are set up wrong.
Damaged pilot assembly.
High temp limit swtich interrupts
power to appliance.
High temp limit switch not wired
correctly. 6V transformer not
plugged into junction box. 6V
power supply jumper wire is not
plugged into IFT-ECM.
Corrective Action
Verify incoming gas line ball valve is 'Open'. Verify inlet pres-
sure is within requirement for gas type used. Contact gas sup-
plier.
Verify wiring, check valve harness black wire is securely
grounded to metal chassis.
Check pilot valve solenoid kick and hold voltages during igni-
tion cycle. Kick V should be >1 V, hold V minimum 0.26 V. If
voltages are OK, replace gas valve.
Check if white sense lead is securely connected to 'S' terminal
of IFT-ECM. Check resistance of sense lead between sense
rod tip and connector to IFT-ECM, should be less than 1 ohm
- if not, replace pilot assembly. Check system ground, ensure
black valve harness wire is securely attached to metal chassis.
Check wiring for damage. With system OFF, check resistance
between tip of sense rod and pilot hood, should be resistance
(>1 M-ohm).
With glass assembly installed, verify pilot flame is engulfing
flame sense rod on pilot assembly. Verify inlet gas pressure
is correct for gas type. Polish flame sense rod with fine steel
wool to remove any contaminants that may have accumulated.
Check if green wire in valve harness is connected to green
main valve solenoid. Check main valve solenoid resistance,
nominal is 60 ohms. If open or shorted, replace valve. Verify
valve inlet pressure is correct for gas type.
Power Vent blower defective - check wiring to IFT-ACM, check
if blower is working. Check if PV pressure switch is connected
to brown and black wire in 6-pin valve wire harness. Check if
pressure switch is closed (shorted) when PV blower is running.
Refer to PV troubleshooting instructions.
Check if white sense lead is securely connected to 'S' terminal
of IFT-ECM. Check resistance of sense lead between sense
rod tip and connector to IFT-ECM, should be less than 1 ohm
- if not, replace pilot assembly. Check system ground, ensure
black valve harness wire is securely attached to metal chassis.
Check wiring for damage. With system OFF, check resistance
between tip of sense rod and pilot hood, should be resistance
(>1 M-ohm).
With glass assembly installed, verify pilot flame is engulfing
flame sense rod on pilot assembly. Verify inlet gas pressure
is correct for gas type. Polish flame sense rod with fine steel
wool to remove any contaminants that may have accumulated.
Verify no soot deposits are in sense rod to pilot hood gap.
Remove and re-install logs per the log placement instructions.
Verify the pilot assembly ceramic insulator around the flame
sensing rod is not cracked, damaged or loose. Check resis-
tance between tip of sense rod and IFT-ECM connector, should
be less than 1 ohm. Replace pilot assembly if damage is de-
tected.
This appliance is equipped with a temperature limit switch
which is located above the appliance firebox. This switch is
used to protect against reverse draft or flue blockage on b-vent
appliances. Verify appliance is drafting properly and termina-
tion cap is clear.
Verify 6V transformer is plugged into junction box. Verify high
temp limit switch wires and 6V transformer are connected to
2179-300 jumper wire. Verify 2179-300 jumper wire is plugged
into IFT-ECM. Reference installation manual for wiring dia-
gram.
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