problem
the humidifier does not turn on
the humidifier does not start
operation
the humidifier loads up water
without producing steam
the thermal-magnetic overload
switch is activated
the humidifier wets the duct
the humidifier wets the floor below
causes
1. no electrical power;
2. external switch of the humidifier in position
0 (open);
3. control connectors badly connected;
4. broken fuses;
5. transformer fault
1. remote ON/OFF contact open (relay/terminals
AB – AB or 7I – 8I);
2. the humidistat has not been connected correctly;
3. humidistat fault
4. control signal not compatible with the type set
5. value measured by the probe/s higher than the
corresponding set point
1. too high steam inlet counterpressures;
2. inlet filter to the clogged cylinder;
3. limestone in the supply tank;
4. drain solenoid valve malfunction
1. thermal-magnetic overload switch is under-rated
2. over-current at the electrodes
1. the distributor is not installed correctly (too near
the top of the duct or the condensate return is
blocked);
2. system over-sized;
3. humidifier active when the fan in the duct is off
1. the humidifier drain is blocked;
2. the supply water or overflow circuit has leaks;
3. the condensate drain pipe does not bring the
water back to the supply tank;
4. the steam outlet pipe is not properly fastened to
the cylinder
10.4 Troubleshooting table
solution
1. check the protection devices upstream from the
humidifier and the presence of power;
2. close the switch on the panel: position I;
3. check that the connectors are properly inserted in
the terminal block;
4. check the condition of fuses F1/F2/F3;
5. check that the voltage across the secondary
winding of the transformer is 24Vac
1. close ON/OFF contacts (relay/terminals AB – AB or
7I – 8I);
2. check the external connection;
3. replace the humidistat
4. set parameters A0, A2-A9 correctly
5. check the values of the set point St and P7
1. check that the steam inlet pipe is not folded or
choked;
2. clean the filter;
3. clean supply tank;
4. check the anomalous presence of 24Vac on drain
solenoid valve and/or drain solenoid replacement
1. check that the thermal-magnetic overload switch is
rated for a current of at least 1.5 times the rated
current of the humidifier
2. see description for alarm EH
1. check that the steam distributor is installed
correctly;
2. decrease the steam production set on the control;
3. check the connection of the device (flow switch
or differential pressure switch) slaving the humidifier
to the ventilation in the duct (terminals AB - AB or
7I – 8I)
1. clean the drain in the bottom tank;
2. check the entire water circuit;
3. check the correct position of the condensate
drain pipe in the supply tank;
4. check the fastening of the pipe clamps on the
steam outlet
69
humiSteam - cod. +030221914 rel. 5.2 - 07.11.2005
Table. 10.4.1