Specifications

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Table 9 - Tubular Blower Troubleshooting Guide
SYMPTOMS POSSIBLE CAUSE(S) CORRECTIVE ACTION
A. Flame pops back. 1. Burner orifi ce too small. 1. Check with local gas supplier for proper orifi ce
size and replace. Refer to "Gas Input Rate."
B. Noisy Flame. 1. Irregular orifi ce causing whistle or resonance.
2. Excessive gas input.
1. Replace orifi ce.
2. Test and reset manifold pressure (see Table
4 - "Gas Piping Requirements").
C. Yellow tip fl ame (some yellow
tipping on LP gas is permissible).
1 Clogged main burners.
2. Misaligned orifi ces.
3. Insuffi cient combustion air.
4. Possibly over fi red.
1. Clean main burner ports.
2. Replace manifold assembly.
3. Refer to "Installation - Clearances" and
"Venting" to ensure unit is properly mounted
and vented.
4. Check gas input and manifold pressures.
D. Floating fl ame. 1. Blocked venting.
2. Insuffi cient combustion air.
3. Blocked heat exchanger.
4. Air leak into combustion chamber or fl ue
collector.
1. Clean fl ue. Refer to "Installation."
2. Clean combustion air inlet openings.
3. Clean heat exchanger. Refer to "Installation."
4. Determine leak and repair accordingly.
E. Gas odor 1. Gas leak. Shut off gas supply immediately!
2. Leaking gas test port on valve.
3. Blocked heat exchanger.
4. Blocked fl ue collector.
5. Negative pressure in the building.
1. Inspect all gas piping and repair accordingly.
2. Check to ensure gas test ports are sealed.
3. Clean heat exchanger. Refer to "Installation."
4. Clean fl ue collector. Refer to "Installation."
5. See "Installation."
F. Delayed ignition. 1. Improper ground.
2. Bad or broken spark cable.
3. Faulty control.
4. Pressure regulator set too low.
5. Main burner orifi ces dirty.
6. Improper venting.
1. Check grounding wires and spark bracket
connections.
2. Inspect spark cable connections and cuts.
Replace if necessary.
3. Check to ensure spark is energized after pre-
purge period.
4. Test and reset manifold pressure.
5. Clean or replace orifi ces.
6. Refer to "Installation."
G. Failure to ignite. 1. Gas leak. Shut off gas supply immediately!
2. No power supply to unit.
3. Thermostat not calling.
4. Defective high limit.
5. Defective draftor prove switch.
6. Defective spark ignitor, gas valve, thermostat
or transformer.
7. Loose wiring.
8. Improper ground.
9. Improper thermostat or transformer wiring.
1. Open all manual valves, check for leaks.
2. Turn on power supply, check fuses and
replace if bad.
3. Turn up thermostat. Check for 24V on
terminals R and W1 on terminal strip.
4. Check switch for continuity if open with no
heat present; replace.
5. Check switch operation to ensure switch
closes after draftor purge period. If it does not
make, check tubing connections for blockage.
6. Check for continuity and voltage in safety
and control circuits; replace an item where
continuity or voltage not found.
7. Check all wiring per diagram.
8. Check all ground wires and connections.
9. Check both for wiring according to diagram;
check for 24V at gas valve terminals during
trial for ignition period. If present and valve
does not open, replace valve.