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Designs, materials, weights and performance ratings are approximate and subject to change without notice. Visit
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Control Humidistat
The Series EHU-800 is capable of accepting controls signals from a humidistat, with the following characteristics:
To adapt the EHU-800 to these different types of control humidistats on the printed circuit board must be manually changed
and the humidistat must be wired to the appropriate connections of terminals 1, 2 with a 0,75mm² maximum flexible cable
for the connection.
Wall Mounted Control Humidistat:
Wall-mounted humidistats are usually installed 4 ft. to 5 ft. above floor level. Often, the best location is beside a thermostat
that controls temperature in the same space that is to be humidified, if that location meets the following criteria:
The control humidistat should be located where it will be exposed to the average air condition of the space to be humidified.
Avoid areas of restricted air circulation, or locations where the sensor will be subjected to air drafts, localized heat, or
moisture sources.
Locations near coffee machines, computer blower outlets, doors to other rooms, or windows that can be opened are not
suitable.
Duct Mounted Control Humidistat:
A duct mounted high limit humidistat is recommended to prevent over-saturation of the duct air. Use an on-off controller
that opens on fault (high humidity). Humidistat should be set for a maximum of 90% RH. Alternately, a modulation high limit
humidistat may be used on applications such as variable air volume (VAV). Locate the high limit humidistat approximately
10’ (3m) downstream of the dispersion manifold. If 10’ (3m) is not available, consult the factory.
Airflow Switch
An airflow switch is recommended to deactivate the humidifier when there is insufficient air flow in a duct system. A duct
pressure switch is preferred as an airflow sensor. The pressure switch should open on insufficient airflow (opens on fault).
Airflow switch should be mounted in supply air duct upstream of humidifier dispersion. Complete installation and wiring
instructions are contained in the duct pressure switch package. The Airflow switch has to be connected in series with the
humidistat between the terminal block 1&2.
NOTE: LIMIT SWITCHES (HIGH LIMIT AND AIRFLOW SWITCHES) OPEN ON FAULT
