Test method
Outcome
Step 1
1. Disconnect the high pressure hose (+) from the switch.
2. Start the burner.
After testing, reconnect the high pressure hose.
Boiler pre-purging begins. The burner
must shut down before the pre-purge
cycle is completed.
Error code 28 and a text
Air pressure off
appear on the display.
Step 2
1. Disconnect the low pressure hose (-) from the switch.
2. Start the burner.
After testing, reconnect the low pressure hose.
Boiler pre-purging begins. The burner
must shut down before the pre-purge
cycle is completed.
Error code 28 and a text
Air pressure off
appear on the display.
Step 3
1. Start the burner. Wait until the start-up sequence is
finished.
2. After the start-up is completed, rotate the setting wheel on
the switch towards the maximum setting.
After testing, return the setting wheel to its original position.
The burner should shut down before the
maximum setting.
Error code 28 and text
Air pressure off
appear on the display.
Step 4
1. Start the burner. Wait until the start-up sequence is
finished.
2. After the start-up is completed, disconnect both pressure
hoses from the switch.
After testing, reconnect both hoses to the original positions.
The burner should shut down
immediately after hoses are
disconnected.
The burner will shut down immediately.
Error code 28 and text
Air pressure off
appear on the display.
Gas pressure switches
For instructions on adjusting the switches, see section
Adjusting gas pressure
switches
.
Gas pressure, minimum
Test method
Outcome
Step 1
1. Rotate the setting wheel on the switch to its maximum
value.
2. Start the burner.
After testing, return the setting wheel to its original position and
reset the switch.
Boiler pre-purging begins. The burner
must shut down before the pre-purge
cycle is completed.
Error code 2F and the text
Gas Pressure
has dropped below minimum Limit
appear on the display.
Step 2
1. Start the burner. Wait until the start-up sequence is
finished.
2. Rotate the setting wheel on the switch towards the
maximum value while the burner is running.
After testing, return the setting wheel to its original position and
reset the switch.
The burner should shut down before the
maximum setting.
Error code 2F and the text
Gas Pressure
has dropped below minimum Limit
appear on the display.
Gas pressure, maximum
Test method
Outcome
1. Start the burner. Wait until the start-up sequence is
finished.
2. Drive the burner to maximum capacity.
3. Rotate the setting wheel on the switch towards the
minimum value while the burner is running.
After testing, return the setting wheel to its original position and
reset the switch.
The burner will shut down before the
minimum setting.
Error code 30 and text
Gas Pressure
has exceeded maximum Limit
appear
on the display
M4263 2206EN
95 (102)
