Nortec NH Series User Manual
Page 71
10-40
Page 64
2008-08-28
Table 3. NH System Messages (cont)
NHTC Display Message
LED state
System Action
Symptom Diagnosed
W27: Safety loop instability
YEL
The safety loop is interrupting
humidifier operation.
A security control is causing the safety
loop to switch on and off too rapidly.
W28: demand signal instability
YEL
The demand signal is swinging
from low demand to high
demand too quickly.
The demand signal is unstable.
W29: limit signal instability
YEL
The limit signal is swinging from
low demand to high demand too
quickly and the humidifier
cannot respond.
The limit signal is unstable.
W30: Modbus remote disable
YEL
The humidifier is being
controlled via the network, not
locally.
The humidifier has been disabled by a
network message.
W43: Keep warm active
YEL
This is a customer selectable
feature to keep the cylinder
water warm.
The humidifier is in standby mode.
The cylinder may energize at any
time.
W44: Demand signal short
cycling
YEL
The cylinder automatically
reduces the humidifier output to
stabilize operation.
The demand signal is cycling on and
off too frequently.
W45: safety loop short cycling
YEL
The cylinder automatically
reduces the humidifier output to
stabilize operation.
The demand signal is cycling on and
off too frequently.
W46: RH high warning
YEL
An alarm indication is
generated.
RH levels higher than the limit set
have been detected. The humidifier
should not be operational with this
warning activated.
W47: RH low warning
YEL
The humidifier is operating and
an alarm indication is
generated.
RH levels lower than the limit set have
been detected. The humidifier should
be operational with this warning
activated.
W49: wrong cylinder installed
YEL
An alarm indication is
generated.
The cylinder installed is not the
recognized type for the humidifier.
E50: Modbus Timeout
RED
Systems shuts down.
Time window for Modbus has elapsed.