1
126 Bailey Road, North Haven, CT 06473 • Phone (203) 776-0473 • FAX (203) 764-1711 •
www.hydrolevel.com
MODEL OS-100
Outdoor Sensor Kit
for Model 3200-
Plus
and
Model 3250-
Plus
Fuel Smart HydroStats
manufactured after 0/0/11
WARNING
Electrical shock hazard.
To prevent electrical shock, death or
equipment damage, disconnect power supply before
installing or servicing control. Only qualified personnel may install or service this control in
accordance with local codes and ordinances. Read instructions completely before proceeding.
CAUTION
To prevent serious
burns, boiler
should be thoroughly cooled before installing or
servicing control.
Kit Includes
• Outdoor Reset Sensor with 9-foot cable
• Sensor mounting bracket with 2 screws and 1 wire clip
• Two spade connectors
• Knockout wire bushing
This document provides instructions for connecting the Hydrolevel Outdoor Sensor Kit to an installed
Fuel Smart HydroStat control. For information on installing the HydroStat control, please refer to the
installation instructions provided with the control or log onto www.hydrolevel.com.
Before installation, determine the
proper location for the sensor
• Sensor should be mounted on the
northern outside wall of the house,
shielded from direct sunlight.
• Sensor should be installed high
enough off the ground to protect
it from accidental damage or
drifting snow.
• Sensor should be installed away
from potential heat sources
such as exhaust fans, windows,
or doors.
WARNING
Frozen pipes/water damage.
Central heating systems are prone to shut down as a result of power or fuel outages,
safety related fault conditions or equipment failure. Installation of freeze protection monitoring or other precautions
is recommended for unattended dwellings in climates subject to sustained below-freezing temperatures.
