CleaverBrooks ProFire Q Series, Installation Operation & Maintenance

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750-437
Q Series Full Modulation
3-5
Operation
{Ph70} = The safety shutoff valves are de-energized/closed and the burner's "Fuel" lamp turns off.
{Ph72} = Traveling to post-purge position - Airspeed ramps up to high-fire air delivery rate
{Ph74} = Mandatory-post-purge time - High-fire air post-purges the heat-exchanger for the minimum-time
requirement. The display shows {Ph74 XX.X} where “XX.X” is the post-purge countdown timer in seconds.
{Ph78} = Optional-post-purge time - Additional post-purge time can be added via parameter adjustment.
{Ph10} = Home Run Position. Following post-purge, the burner motor stops. The gas actuator positions to home
which is the actuator's self-check of its optic position sensors.
• Burner returns to standby Phase 12, the AZL displays {OFF} and is ready for startup on the next call for heat.
Note: LOW WATER - If a low-water condition occurs, the burner shuts down as in “Automatic Shutdown ” and the
AZL displays {OFF}. When the water level is restored and the low-water safety device resets. Provided all other
recycling limits are made and the burner switch is on, the burner will fire again when the operating control
contacts make (receives a new “call for heat”).
3.2.6 — Manual Shutdown
To manually shut off the burner:
• Turn the burner switch to OFF. The burner shuts down as in “Automatic Shutdown.”
• When the burner displays {OFF}, close the gas train's shutoff and main leak-test manual valves.
Automatic operation can not resume until the operator has determined it is safe to operate the system and
returns the gas valves to their open position and turns the burner switch to ON.
3.2.7 — Safety Shutdown
A safety-loop failure presents as an LMV3 error code 22 where the display alternates {Loc.c: 22} and {Loc.d:
X} (“x” being a diagnostic code value). A flame failure (loss of flame signal) presents as an LMV3 error code 93
where the display alternates {Loc.c: 93} and {Loc.d: X}. Either open safety-loop or loss-of-flame-signal
condition will cause the LMV3 to rapidly de-energize the safety-shutoff-fuel valves and the blower motor.
Shutdowns may result from motor overloading; low water; interruptions in either fuel or power supply; insufficient
combustion-air-pressure; tripped circuit breakers; blown fuses; or other interlock devices.
A safety shutdown will illuminate the burner's red “FAILURE” light and (if so equipped) energize an audible
alarm.
The failure's root cause must be determined and corrected before any attempt is made to restart the burner.
Gas pressure fault - If a high or low gas pressure condition occurs during burner operation, the burner shuts down
as in “Automatic Shutdown.” The AZL presents a fault indication and error code 20 condition by alternating
{Loc.c: 20} and {Loc.d: X} in the display. The pressure condition must be corrected and the respective gas
pressure switch is manually reset before attempting a burner restart.