morse AHT 20 Manuel D'instructions page 26

DewPoint too low.
Excessive pressure
drop within the dryer.
The dryer doesn't
drain the condensate.
The dryer
continuously drains
condensate.
Water within the line.
Where installed - The
P high-pressure
A
switch has been
activated.
Where installed- The
P low-pressure
B
switch has been
activated.
Where installed -
The T safety thermo-
S
switch has been
activated.
DMC14- The LED
of the
instrument is on or
flashes to indicate
alarm situations.
The fan is always ON - P
The Hot Gas By-pass Valve is out of setting - contact a refrigeration engineer to restore
the nominal setting.
Ambient temperature is too low - restore de nominal condition.
The Pre-Filter (FTP Series – 3 micron) is clogged - replace the filter element (cartridge) -
Refer to the instructions in the user's and maintenance manual of the filter.
The dryer doesn't drain the condensate - see specific point.
The DewPoint is too low - the condensate is frost and blocks the air - see specific point.
Check for throttling the flexible connection hoses.
The condensate drain service valve is closed - open it.
Verify the electric wiring.
The DewPoint is too low - the condensate is frozen - see specific point.
Bekomat drainer is not operating correctly (see para 5.17 MAINTENANCE
BEKOMAT)
Drainer is dirty – (see para 5.17 MAINTENANCE BEKOMAT)
The dryer doesn't start - see specific point.
Where installed - Untreated air flows through the by-pass unit - close the by-pass.
The dryer doesn't drain the condensate - see specific point.
DewPoint too high - see specific point.
Check which of the following has caused the activation :
1. The ambient temperature is too high or the room aeration is insufficient - provide
proper ventilation.
2. The condenser is dirty - clean it.
3. The condenser fan doesn't work - see specific point.
Reset the pressure-switch pressing the button on the controller itself - verify the
dryer for correct operation.
The PA pressure switch is faulty - contact a refrigeration engineer to replace it.
There is a leak in the refrigerating fluid circuit - contact a refrigeration engineer.
The pressure switch restores automatically when normal conditions are restored -
check the proper operation of the dryer.
Check which of the following has caused the activation :
1. Eccessive thermal load – restore the standard operating conditions.
2. The inlet air is too hot - restore the nominal conditions.
3. The ambient temperature is too high or the room aeration is insufficient - provide
proper ventilation.
4. The condenser unit is dirty - clean it.
5. The fan doesn't work - see specific point.
6. There is a leak in the refrigerating fluid circuit - contact a refrigeration engineer.
Reset the thermo-switch by pressing the button on the thermo-switch itself – verify
the correct operation of the dryer.
The T thermo-switch is faulty - replace it.
S
The LED flashes because the DewPoint is too high – see specific point.
The LED flashes because the DewPoint is too low - see specific point.
The LED flashes because the probe is faulty or interrupted, the instrument
displays the message "PF" (Probe Failure) – replace the probe.
pressure switch is faulty - replace it.
V
GB