Installation and Maintenance
EHU-600 Series Humidifiers
20
Another method of forcing a 100% demand is to remove the
controller input signal from terminal 6, jumper terminal 13
to terminal 6 with a short piece of wire, and select either
1.9-3.9Vdc or on/off control setting on the main circuit board.
10. While the tank is filling, open terminals 2 and 24 with a screw-
driver, loosening and removing the jumper. The fill will stop and the
"Tank Off" light will come on. Replace jumper; within 10 seconds
the contactor will pull in and the fill will resume.
11. Repeat with terminals 3 and 23. The response will be identical to
Step 10.
12. Let the unit continue to fill and allow to boil.
a.
If the water level reaches within 4" of the steam generator
tank top, the high level float switch will block the fill, and
illuminate the "Tank Full" light. This is normal on relatively
pure water, but to complete the start-up testing, push and hold
the drain switch to drain 1/2 of the tank, then, with power off,
add one pinch (1/4 teaspoon) of salt to the fill cup. This should
allow the water to boil by increasing the water's conductivity.
b.
If "Tank Full" light illuminates with water level below midway
point in the tank, the back pressure due to duct static or steam
dispersion piping is too high. Consult factory.
13. On typical beginning fill, after the fill stops, using an ammeter, the
tank leads will each be drawing between 35-40% of "nominal amp
rating" at this point. (See unit label for nominal amp rating.)
14. Press the drain switch. Verify that the unit is drawing freely. Be
sure the drain line is well pitched and is 1" size copper pipe. Do
NOTE use PVC pipe.
15. Install the humidstat element, or verify that it is in place.
16. Verify that the humidity set-point is at the desired value.
17. Blow "humidly" on the humidstat element. The following should
happen:
a.
The demand meter will go to zero.
b.
The unit will shut down, lighting the "Tank Off" light.
c.
The unit may energize again after the sensor "dries" out.
The demand meter indicates the humidstat signal, so once
the sensor "dries out" the demand will climb back to 100%
(maybe less if the humidity level is within the control range of
the humidity setting.)
18. Reconnect the air proving switch to terminals 2 and 24. Verify
that the air proving switch is wired to that it opens on no air flow
and is closed with air flow (normally open).
