Service Manual

3 Troubleshooting
36
Combustion Analysis Procedure
1. Turn the main power off to the water heater by placing the
“On/Off” switch in the OFF position.
2. Remove the flue temperature sensor from the flue pipe
connection. Note: Combustion measurements will be made
at this point.
3. Turn the main power on to the water heater by placing the
“On/Off” switch in the ON position.
4. Place the water heater into the active position by pressing
the RIGHT SELECT [ON] key (see page 5).
5. Locate the pinhole button below the RESET button on the
display board (see page 5). Insert a thin wire (such as a
paper clip) into the hole and press the button once and hold
for 5 seconds to place the water heater into Service Mode.
In Service Mode the water heater will fire at ignition speed
and will then modulate up to full fire.
6. Insert the probe from a combustion analyzer into the hole
left by the removal of the flue temperature sensor.
7. Once the water heater has modulated up to full fire, measure
the combustion. The values should be in the range listed in
Table 3G above. The CO levels should be less than 150 ppm
for a properly installed unit.
If the combustion is not within the specified range, reference
the chart below for possible causes and corrective actions.
Table 3H Troubleshooting Chart - Combustion Levels
POSSIBLE CAUSE CORRECTIVE ACTION
Vent/Air Intake Length
or Obstruction
• Refer to Section 3 - General Venting of the Armor Water Heater Installation and Operation
Manual for the proper venting and air intake methods for the Armor water heater.
• Check for obstructions at the vent/air intake terminals.
Gas Supply Pressure
• Refer to Section 7 - Gas Connections of the Armor Water Heater Installation and Operation
Manual for the proper gas supply for the Armor water heater.
Dirty/Damaged Burner
• Refer to page 22 of this manual for burner removal and cleaning procedures.
• Replace burner if necessary.
Gas Valve Adjustment
• Refer to pages 37-38 of this manual for the gas valve adjustment procedure.
Table 3G Flue Products
Natural Gas Propane
CO
2
O
2
CO
2
O
2
8.0% - 10% 3.0% - 6.5% 9.0% - 11% 4.1% - 6.9%
8. Once the combustion analysis is complete, test the safety
shutoff device by turning the manual shutoff valve to the
OFF position and ensuring that the water heater shuts down
and registers an alarm. Open the manual shutoff valve,
reset the control, and return to Service Mode.
9. Turn the main power off to the water heater and replace the
flue temperature sensor into the flue pipe connection.
10. Place the water heater back into normal operation.
You must replace the flue gas temperature
sensor to prevent flue gas spillage into the
room. Failure to comply could result in
severe personal injury, death, or substantial
property damage.
 WARNING
Service Manual