Specifications
Installation & Maintenance Manual__________ 
54
15. Troubleshooting Table 
problem  cause  solution 
The controller does not 
work. 
1. power is not supplied; 
2. external interrupt is off; 
3. poor electrical connection; 
4. blown  fuse; 
5. bad  transformer; 
1. check that the correct power has been 
supplied; 
2. turn on the external interrupt; 
3. check that the connections to the controller 
terminals are good; 
4. check the condition of the fuses F1/F2; 
5. verify that the secondary of the transformer is 
supplying 24 Vac and fuse F3 is not blown. 
The humidifier won't 
start 
1. ON/OFF contact open (jumper on terminals 7I-
8I); 
2. the regulator/humidity controller or external 
sensor are not connected properly; 
3.  broken sensor/humidistat; 
4. the  configuration  parameters have been 
improperly set; 
5. the ventilation fan has gone out 
1. close the remote ON/OFF (relay terminals 7I - 
8I); 
2. connect the external controller correctly; 
3. check the external signal from these devices; 
4. correctly reprogram the parameters; 
5. reset the unit after the cause of the problem 
has been eliminated; 
The humidifier fills and 
drains with water but will 
not produce steam 
1) Back-pressure during steam outlet 
2) Broken water supply valve flow regulator 
(possible leaks in the hydraulic circuit) 
3) Defective water level control 
4) Cylinder inlet filter blocked 
5) Limestone scales in the fill tank 
6) Broken drain valve 
1) Check that the steam outlet valve is not 
crimped or bent 
2) Replace the drain valve 
3) Clean or replace the water level control if 
necessary 
4) Clean the filter 
5) Clean the fill tank 
6a) Check the presence of 24 Vac on drain valve 
6b) Replace the drain valve 
The humidifier trips the 
external interrupt 
1. the overload protection is incorrectly sized; 
2. short-circuit 
1. make sure the interrupt is sized correctly; it 
must be rated for a current of 1.5 times the 
nominal current and voltage of the humidifier; 
2. check with a meter to discover any short 
circuits and correct them 
The humidifier wets the 
duct 
1) The distributor is not installed correctly 
2) The system is over-sized 
3) Humidification is on when the duct fan is off
1) Check that the steam distributor has been 
installed correctly. (see par. 9.3, page 21) 
2) Decrease the steam production on the 
humidifier control 
3) Connect a trigger from the fan to terminals 7I - 
8I of the On-Off remote (e.g. differential pressure 
switch or flow switch contact) 
The humidifier leaks 
1) The humidifier drain is blocked 
2) The hydraulic circuit is over-full or has 
leaks 
3) The condensation drain pipe does not feed 
into the filler tank 
4) The steam outlet pipe is not properly 
attached to the cylinder 
1) Clean the drain outlet in the bottom tank 
2) Check the entire hydraulic circuit 
3) Check the correct placement of the 
condensation drain pipe in the fill tank. 
4) Check the tightening of the pipe clamp on the 
steam outlet 
Loss of humidity in 
space and no alarms 
displayed on the 
controller 
1) Direct Spark Ignition module has shutdown 
on internal error. 
2) Blockage of intake and exhaust vent pipes 
3) Loss of flame in burner 
1) Turn the power to the unit off 
2) Check for blockages in the intake and exhaust 
vent pipes. 
3) Lower humidity set point to its lowest setting, 
for 30 seconds, and then reset to desired level 










