Lennox CLIMATIC series User Manual page 45

COMMUNICATION
ALARM 004, 005:
FILTERS, CLOGGED OR MISSING
Description
The differential pressure between the treatment unit and the fi lters is too small, although the fan has been running for more than 3
minutes.
• Filters missing: ΔP < safety threhold, (2334)
• Filters clogged: ΔP > safety threhold.(2335)
Action
The alarm is signalling.
Reset
The alarm is automatically deleted once the pressure returns to the authorized operating range.
If Dirty or Missing Filters Alarm keeps active during 168 hours (7 days non stop) the Blower is turned off and locked.
To reset this alarm, the power must be shut off, then the unit restarts for 15 minutes. If no fi lters alarm appears during this 15
minutes, the counter and the alarm is reset to zero, and the unit operate normally. If an alarm occurs during the 15 minutes the unit
is stopped again and need again a power shut off.
This alarm is only for the Roof Top fi lters.
Possible cause(s)
• Filters removed and not replaced,
• Filters clogged,
• Problem with the pressure transmitter wiring,
• Incorrect setting for the safety thresholds (2334) and (2335)
Remedies
• Fit new fi lters,
• Clean or replace the fi lters,
• Check the connections,
• Check the settings (2334) and (2335).
ALARM 011, 012:
ELECTRICAL HEATERS, OVERHEATING
Description
The status of the safety thermostat of the electrical heater signals an oveheating on the system.
Action
Immediate shut down of the electrical heaters.
Reset
Manual reset.
Possible cause(s)
• Problem with wiring of the electrical heaters,
• Air system obstructed or closed,
• Filter clogged,
• Belts broken.
Remedies
• Check the connections of the electrical heaters,
• Check the air system,
• Clean the fi lters,
• Replace the belts.
CLIMATIC RT_UNITARY-IOM-1508-E • 43 •