Description Of Controls - Lennox LXTFZ01M Manual

INTRODUCTION
This embedded electronic regulation device is a digital thermostat to control
the temperature in rooms heated or cooled with fan coils. It provides a
continuous proportional control over the valves and speed of the fan on the
0..10V outlets in order to control the room's temperature in a more convenient
way.
The device is also fitted with three ON/OFF relay outputs that can be used
to control a fan with three speed settings or two ON/OFF actuators. The room
temperature can be detected by the internal or remote probe (optional feature).

DESCRIPTION OF CONTROLS

The user has five buttons available to control the thermostat.
- Key " " (On/Off)
This button is used to turn on and off the controller: when the controller is turned
off the display does not show the temperature, yet some symbols could still be
turned on to show the active outputs.
If the thermostat is configured in the "Economy" function (P18), the " " button
activates/deactivates this status according to the following diagram:
ON
- " " button (Speed)
This button changes the set fan speed.
When the " " button is pressed, the fan speed changes according to the
following cycle:
LXTFZ01M-IOM-1502
where 1, 2 and 3 mean the three fixed fan speeds meanwhile AUTO means
the automatic fan speed.
More precisely 1 means the lowest speed, 2 the medium speed and 3 the
fastest. When the controller is set on one of the three mentioned speeds,
the fan will be activated when necessary always at that fixed speed.
Whenever the automatic speed is set instead, the controller will activate
the fan at a speed as much high as the difference between the desired
room temperature against the current one.
If the thermostat is configured to control the fan with the 0..10V
proportional output, it will be possible to configure the three fixed speeds
to the desired values in the parameters C11, C12 and C13.
Parameter C10 is used to customize the speeds that ca be recalled with
the " " button and also the OFF status can be enabled, which allows the
user to keep the fan off.
- Key " " (Menu)
This button is used to change the display readout mode: when depressed
once it makes the display show the set-point temperature.
In case the controller is configured to show the delivery water temperature,
this value will be displayed with a further button depression.
When changing the readout, the controller informs the user about the
OFF
temperature shown according to the following table:
Set-point temperature
Delivery water temperature
Repeatedly press the button to cyclically display the various temperatures.
When inactive for a few seconds the display returns to room temperature.
- "" and "" buttons
These buttons set the desired room temperature (set-point) and the
41