Laars MASCOT LX, Service Manual

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Mascot LX Service Manual
The System sensor is mounted in the circulating loop, and provides the input for the
CH (Central Heating) function. This type of sensor can fail in either an “open” or
“shorted” condition, or may become inaccurate.
If the SIT controller detects a problem with the system sensor, it will present a fault
message.
To check the sensor for accuracy, see Section B9.
The DHW sensor is mounted in the DHW loop, and provides the input for the DHW
(Domestic Hot Water) function. This type of sensor can fail in either an “open” or
“shorted” condition, or may become inaccurate.
If the SIT controller detects a problem with the DHW sensor, it will present a “n05”
fault message. For more information, see Section B25 or B27.
To check the sensor for accuracy, see Section B9.
System Sensor
DHW Sensor
The Outdoor sensor is mounted outside the heated space, and provides the input for
the Outdoor Reset function. This type of sensor can fail in either an “open” or “shorted”
condition, or may become inaccurate.
If the SIT controller detects a problem with the Outdoor sensor, the controller will
operate at a setpoint of 140°F or the value of Installer Parameter P62 (High Setpoint
for Heat Curve), whichever is lower.
For more information on Outdoor Reset, see Section B18. To check the sensor for ac-
curacy, see Section B9.
Note - By default, the warm weather shutdown feature is always active when the out-
door sensor is installed.
Outdoor Sensor
B5
B6
B7