Installation and Maintenance
EHU-600 Series Humidifiers
29
Diagnostics
The EHU-600 has a diagnostic function which serves as a trouble-
shooting aid. The diagnostics will check all the output circuits: fill valve,
drain valve, contactor, and display lights to make sure they are working.
It then shows the status of all input circuits: fan interlock switch, high
limit duct humidistat, high water switch or probe, and humidistat demand
signal.
To initiate the diagnostic routine:
a.
Turn water supply off.
b.
If the tank contains water, press and hold Manual Drain switch
until the tank is empty. Drain light will not come on.
c.
Press and hold the Tank On/Off switch until the Fill light begins
to blink (approximately 15 seconds). The Tank Off light will go
off if it is on or go on if it is off.
d.
Release the switch when the Fill light begins to blink. This
signals that the diagnostics routine has begun.
For the purpose of the diagnostic function, the lights on the front panel
of the humidifier correspond to assigned input and output circuits. Note:
The Power light remains on during the whole diagnostic routine and
does not correspond to any circuit.
1.
Output Circuits
The first half of the diagnostics routine checks the output circuits. Each
light on the humidifier panel will flash on and off twice, in order, from top to
bottom.
When a light comes on, you will hear the corresponding valve or
contactor open and close. Chart 29-1 shows the output circuits in the
order they are tested.
Chart 29-1
Light
Corresponding Output Circuit
Fill
Fill Valve
Drain
Drain Valve
Tank Full
No related output(a)
Tank Off
Contactor(s)
Demand Meter
No related output(b)
a.
The Tank Full light indicates a high water condition. The output
portion of the diagnostics checks whether this light is
functioning.
b.
The output portion of the diagnostics indicates whether the
demand meter lights are functioning.
