Evaporator Freezing Protection - Lennox CLIMATIC 50 User Manual

EVAPORATOR FREEZING PROTECTION

Description
This fault signal is activated on units chilling water without frost protection additives (Water without Glycol or
Brine) and with thermostatic expansion valves.
One compressor from the considered circuit n has been running for at least 2 minutes and the saturated
temperature TBPn is lower than the set point 3421 for more than 5 seconds (for units filled with R407c).
This safety feature is disabled for 2 minutes after start-up or stop of a compressor or a fan on the considered
circuit.
With:
TBPn %
3421
%
Action
$ Immediate shutdown of circuit n
$ Fault signal sent to the control display.
$ The remote fault signal is delayed by 6 minutes
Reset :
The first 3 faults are automatically reset
After three faults the circuit n can only be restarted by a manual reset
Note:
Fault counter is cleared and reset every day at 10 am, as long as the maximum number of faults has not
been reached.
Possible causes
Faulty LP pressure sensor
Faulty wiring or loose sensor connection.
Insufficient water flow rate in the evaporator.
Clogged evaporator
Check set points
CLIMATIC 50, user manual – Chillers ranges
Fault Code: 1
Evaporating Temperature of circuit n - dew point (°C)
Minimum Evaporating Temperature (°C)
n8
Solving the problem
Replace the pressure sensor.
Check pressure sensor connections and wiring.
Check flow rate and adjust flow switch if necessary.
Clean evaporator.
Replace pressure sensor.
CL50-CHILLERS/IOM/0906-E
FAULT CODES
34
34