LAARS S8Ext - Installation Manual - Manual (Page 8)

Page 8 LAARS Heating Systems
INSTALL THE SENSORS
SYSTEM SENSOR INSTALLATION
LOCATING THE SYSTEM SENSOR
• Put the System sensor approximately 10' feet past the last heating/cooling unit
on the common supply header but before any major takeoffs.
• The sensor must be located where it sees the output of all the stages. If a unit
is piped so that the sensor does not see its output, the S8 will not sequence the
units correctly.
• Only use a Standard Brass Tube sensor (CA002400 or equivalent).
• The sensor wires can be extended up to 500' using a shielded 2-conductor
cable (Belden #8760 or equivalent). Do not ground the shield at the sensor
but at the panel using one of the terminals marked with an “O”.
• Do not run sensor wires in conduit with line voltage wiring.
IMMERSION HEATING SYSTEM SENSOR (HSS) INSTALLATION
• Install a 3/8"ID immersion well (CA002500 or equivalent).
• Insert the sensor probe of the supplied sensor into the well.
STRAP-ON HEATING SYSTEM SENSOR (HSS) INSTALLATION
• Strap the sensor to the pipe using metal clamps. Do not over tighten the
clamp.
• Strap pipe insulation around the sensor and pipe.
Immersion Well
3/8" ID 1/2" NPT
Heating System
Sensor
Common Supply Pipe
Sensor Probe
Immersion Heating System Sensor
Shield
Common Supply Pipe
Sensor Probe
Strap-On Heating System Sensor
Shield
Pipe Insulation
Immersion Well
3/8" ID 1/2" NPT
Heating System
Sensor
Common Supply Pipe
Sensor Probe
Immersion Heating System Sensor
Shield
Common Supply Pipe
Sensor Probe
Strap-On Heating System Sensor
Shield
Pipe Insulation
CAUTION
If the System Sensor can not sense the
correct system water temperature being
supplied to the building, the S8 will not
provide comfortable heat/cool levels. Be
sure that it is located on a main supply
pipe which can not easily be isolated
from the system.
OUTDOOR SENSOR INSTALLATION
• Only use the Laars sensor included with the unit.
• Locate the sensor in the shade on the north side of the building. The sensor
should never be in direct sunlight.
• Be sure the location is away from doors, windows, exhaust fans, vents, or
other possible heat sources.
• The sensor should be mounted approximately 10' feet above ground level.
• Mount the sensor clip base to the outside of the building. Insert the sensor in
the middle and snap close the clip on the sensor.
• The sensor wires can be extended up to 500' using shielded 2-conductor cable.
Do not ground the shield at the sensor but at the control using the terminal
marked with an “O”.
• Do not run sensor wires in conduit with line voltage wiring.
WARNING
The S8 is an operating control only. All equipment must have all
safety and limit controls required by code. It is the responsibility
of the installer to verify that all the safety and limits are working
properly before the S8 is installed.
CAUTION
Determining the proper location for the Outdoor Sensor is very
important. The S8 will base its operation on the outdoor temperature
information it receives from this location. If the sensor is in the
sun, or covered with ice, its reading will be different from the actual
Outdoor temperature (OD).
10' Minimum
Outdoor Sensor
Low Voltage
Sensor Wires
Sensor Clip