ETL MUA Controls, Installation, Operation And Maintenance Manual

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HMI and Remote Room Sensor Installation
Remote HMI faceplates ( Figure 13) , remote room sensors ( Figure 14 ), and smart controls may be
ordered and shipped separately. These components measure temperature and assist in controlling the
unit. These components should be installed in a safe location, free of influence from external heat sources.
Install sensors in areas indicative of the average room temperature, and away from heat-producing
appliances. HMIs and remote room sensors can be installed directly to industry-standard junction boxes,
either surface mounted or recessed mounted. HMIs have a built-in temperature/relative humidity (RH)
sensor, which is typically used to help control the automatic function of the unit.
The HMI can also be configured to control the unit from a remote location manually. They can be
configured not to use the internal temperature/relative humidity sensor. In this configuration, the sensor in
the HMI is ignored in automatic operation. Multiple HMIs can be connected to one unit for temperature and
R/H averaging. All combination temperature/humidity HMIs will use a vented standoff. Mount the static
pressure tube close to the HMI to obtain proper room conditions.
A max of 4 additional HMIs can be daisy-chained together. Place an End-of-Line (EOL) device in the last
HMI connected.
Figure 13 - HMI with Standoff
Figure 14 - Remote Room Sensor
The room temperature sensor is a 10K ohm thermistor. The
sensor provides constant room temperature to the controller.
It should be installed on a wall somewhere in the room, but
not directly in the HVAC diffuser’s path or close to heat-
producing appliances so that the reading is not affected by
heat.
Room sensors are not required for proper control operation,
but still can be configured as remote sensors or averaging
sensors.
Do not install the room sensor on the ceiling
.
5-1/2”
5-1/2”
J-Box
HMI Standoff
HMI with Built-in
Temperature/Humidity
Sensor
Route static pressure tube close
to the HMI in the space.
Static Pressure Tube
Connected to the High Pressure
Port on Pressure Sensor
Cat 5 Connection
J1 on HMI-1 to J2 on HMI-2