Troubleshooting Guide - Munters R Series Operating And Maintenance Manual

7.1

TROUBLESHOOTING GUIDE

Problem
Power turned on, unit
does not run, and no
indicator lights
Power turned on, unit
does not run, and
indicator lights on
Unit runs in Manual
position but does not
run in Auto.
Humidity is high,
dehumidifier
performance is poor.
Reactivation inlet over
temperature fault
Blower and / or wheel
drive motor is not
running
Manual# I27028
Possible Cause
No power to the unit or
loss of one phase of
power.
Failed fuses
Phases of supply power
are out of sequence.
Humidistat (option) failed.
Humidistat setpoint is
higher than measured
value.
Controlled space is not
completely sealed.
Unit is not operating at
design conditions.
Wheel is clogged.
Wheel is not rotating at
proper speed (8 rph).
Reactivation air flow is
low.
Gas modulation valve
malfunction
High gas supply pressure.
Thermocouple for high
over temperature switch
has failed.
Motor overload has
tripped.
7-2
Recommended Remedy
Check power to the unit.
Determine which fuse failed and why.
Replace fuses if necessary.
Check three phase power monitor and switch
two of the incoming phases if necessary.
Check humidistat wiring, replace humidistat if
necessary.
Reduce humidistat setpoint.
Seal all ductwork.
Make process space vapor-tight.
Consult flow diagram for correct pressure
drops across wheel. See "Maintenance"
Reduce moisture load or temperature to
dehumidifier in order to operate at design
conditions.
Check for leakage in air handler outside of
dehumidifier.
Monitor wheel pressure drop for multiple
revolutions, looking for changes in pressure
drop readings.
Visually inspect wheel. See "Maintenance"
Check wheel drive motor and chain.
Inspect reactivation blower for blockage.
Inspect reactivation blower damper position.
Inspect reactivation filters for clogging.
Check for correct control signal.
Check for mechanical problem with valve.
Check supply pressure.
Check gas pressure regulator setting.
Inspect sensor and wiring. Replace as
necessary.
Inspect blowers and motors for obstructions,
remove obstruction, and reset with button on
starter.
Rev. 2 – 11/22/2017