Combustion Analysis Procedure - Lochinvar FTxl 500 Service Manual

3
Troubleshooting
Table 3-4 (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Boiler Interface
FAULT
120 vac input to the main control board has
Low 24 vac
dropped below 80 vac.
The main control board has detected an
Watch Dog Error
internal fault.
The main control board has detected an
Write EEProm
internal fault.
The main control board has detected an
CRC Parameters
internal fault.
The particular lockout information has been
No Error Stored
lost.

Combustion Analysis Procedure

1. Turn the main power off to the boiler by placing the "On/
Off" switch in the OFF position.
2. Remove the brass plug from the combustion measurement
port inside the flue collector.
measurements will be made at this point.
3. Turn the main power on to the boiler by placing the
"On/Off" switch in the ON position.
4. Place the boiler into the active position by pressing the
RIGHT SELECT [ON] key (see page 7).
5. Locate the pinhole button above the RESET button on
the display board (page 7). 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 boiler into Service Mode.
In Service Mode the boiler will fire at ignition speed and
will then modulate up to full fire.
6. Insert the probe from a combustion analyzer into the
combustion measurement port (see FIG. 3-2). There is
a stop underneath the combustion measurement port
to prevent the probe from collecting condensate at the
bottom of the flue collector.
(continued)
DESCRIPTION
NOTE: Combustion
Service Manual
CORRECTIVE ACTION
• Check 120 vac supply to the transformer.
• Check wiring connections at the low voltage terminal
strip.
• Check the wire size/length to remote devices.
• Replace the transformer.
• Cycle power to the boiler.
• Replace the main control board.
• Cycle power to the boiler.
• Replace the main control board.
• Cycle power to the boiler.
• Replace the main control board.
• Press the RESET button.
• Replace the main control board.
Figure 3-2 Combustion Measurement Port
IMG00978
COMBUSTION MEASUREMENT
PORT
47