Install Instructions

93
Combustion Analysis Procedure
1. Turn the main power off to the boiler.
2. Hold the ► plus the▼ button for five (5) seconds to
enter Service Mode.
3. Once the boiler has modulated up to full fire, measure the
combustion. Place the analyzer probe in the fitting on
the flue adapter. The values should be in the range listed
in Table 13-4. The CO levels shall be less than 200 ppm
for a properly installed unit.
If the combustion is not within the specified range,
reference Table 13-5 for possible causes and corrective
actions.
Table 13-5 Troubleshooting Chart - Combustion Levels
POSSIBLE CAUSE CORRECTIVE ACTION
Vent/Air Intake Length
or Obstruction
• Refer to Section 3 - General Venting for the proper venting and air intake methods for the
Noble Fire Tube.
• Check for obstructions at the vent/air intake terminals.
Gas Supply Pressure
• Refer to Section 7 - Gas Connections for the proper gas supply for the Lochinvar Fire Tube.
Dirty/Damaged Burner
• Refer to page 79 of this manual for burner removal.
• Replace burner if necessary.
Gas Valve Adjustment
• Refer to this page of the manual for the gas valve adjustment procedure.
13 Troubleshooting (continued)
Table 13-4 Flue Products
You must replace the cap on the vent
adapter to prevent flue gas spillage into the
room. Failure to comply could result in
severe personal injury, death, or substantial
property damage.
⚠WARNING
Gas valve adjustment procedure
4. Once the combustion analysis is complete, test the safety
shutoff device by turning the manual shutoff switch to
the OFF position and ensuring that the boiler shuts
down and registers an alarm. Turn the manual gas valve
to the ON position and reset the control.
5. Turn the main power off to the boiler and replace the cap
on the sample port.
6. Place the boiler back into normal operation.
Installation & Service Manual
FIRE TUBE
™
Natural Gas
Input
Rate
Target Range
CO
2
O
2
CO
2
O
2
High Fire
9.0% 4.9% 8.5% - 10.5% 2.3% - 5.7%
Low Fire
8.9% 5.4% 8.7% - 9.1% 5.1% - 5.7%
CO levels shall be less than 200 ppm.
Propane
Input
Rate
Target Range
CO
2
O
2
CO
2
O
2
High Fire
10.5% 4.9% 10.0% - 11.0% 4.1% - 5.6%
Low Fire
10.4% 5.4% 10.2% - 10.6% 5.1% - 5.7%
CO levels shall be less than 200 ppm.
If adjustment of the gas valve is deemed necessary, use the
following procedure:
CAUTION
This gas valve is factory set. Under normal
operating conditions this valve should not
need adjusting.
High Fire
Locate the throttle adjustment screw on the gas valve (FIG.
13-2). Using a 2.5 mm hex-key wrench, turn the screw 1/10 to
1/8 turn counterclockwise to increase CO
2
levels or 1/10 to 1/8
turn clockwise to decrease CO levels. After one adjustment
on the valve, follow the Combustion Analysis Procedure of this
manual to measure the combustion.
Low Fire
Locate the bias/offset adjustment screw on the gas valve (FIG.
13-2). Using a 4 mm hex-key wrench, turn the screw 1/10 to
1/8 turn clockwise to increase CO levels or 1/10 to 1/8 turn
counterclockwise to decrease CO levels. After one adjustment
on the valve, follow the Combustion Analysis Procedure of this
manual to measure the combustion.
NOTE: The low fire adjustment responds very slowly. Make
extremely small adjustments and allow the boiler to run for a
couple of minutes between adjustments. Use a combustion
analyzer to check the adjustment effects.
If combustion is still not within the specified range, repeat
the procedure. This procedure SHOULD NOT be performed
more than four (4) times. If after four (4) adjustments and the
combustion is still not within the specified range, revisit the
possible causes in Table 13-5 and call Technical Support before
replacing the gas valve.