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ULTRA-SORB MODEL MP INSTALLATION, OPERATION, AND MAINTENANCE MANUAL
Table 25-1:
Ultra-sorb Model MP troubleshooting (continued)
Problem
Possible cause
Action
Space humidity will not
rise to humidistat set
point
• Steam pressure too low
• Increase.
• Manual steam valve partially closed
• Open.
• Strainer screen partially clogged
• Clean.
• Boiler pressure too low
• Adjust control.
• Pressure reducing valve not accurately
controlling steam pressure
• Repair or replace.
• Boiler pressure swinging too widely
• Adjust controls.
• Incorrect piping
• Repipe. See Page 14.
• Undersized steam piping
• Replace.
• Undersized humidifi er
• Replace valve with larger capacity valve.
• Replace with larger humidifi er.
• Add additional humidifi er.
• Automatic steam valve not fully opening
• Valve packing is adjusted too tightly, loosen and/or
replace packing.
• Adjust valve linkage.
• Recalibrate humidistat.
• Electric control system malfunctioning
• Change transformer.
• Incorrect control circuit voltage
• Replace component(s) to make all components compatible.
• Incorrect control signal
• Replace components.
• Improper wiring
• Rewire.
• Incorrect humidity sensor
• Replace sensor.
• Humidity controller out of calibration or
malfunctioning
• Repair or replace.
• Malfunctioning humidifi er temperature switch
not allowing humidifi er valve to open
• Replace or readjust.
• Pneumatic control system malfunctioning
• Repair or replace.
• Obstructed air line
• Remove obstruction.
• Malfunctioning pneumatic temperature
switch
• Replace switch.
• Air leak in actuator
• Repair or replace diaphragm.
• Compressed air pressure is too low
• Adjust pressure.
Condensate in duct
• Foreign matter preventing valve from closing • Clean or replace valve.
• Humidifi er is mounted too close to internal
devices (dampers, turning vanes, etc.) in
duct
• Move humidifi er tubes to a point further upstream from
internal devices.
• Add more dispersion tubes for shorter non-wetting
distance. Consult DriSteem to determine the total number
of tubes required.
• Non-insulated duct passing through
unheated area (duct surface temperature too
low)
• Insulate ductwork.
MAINTENANCE
Troubleshooting
