White Rodgers HFT2100 Guide

2271-100 HUMIDISTAT
The humidistat is designed for either return air duct or wall mounting.
Packaged in a duct mount configuration, (For this type mounting begin
installation at the section labeled return air duct installation on
page 2.) for conversion to a wall mount configuration simply pull off the
knob and remove the mounting screws and rotate the control 180° and
reattach the mounting base, (For this type mounting begin installation
at the section labeled wall mount installation on page 3.).
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!DANGER
*Do not cut or drill into any air-conditioning or electri-
cal accessories during installation.
*Fatal electrocution is possible if you contact a live
wire.
*Electrical power can cause electrical shock.
*Disconnect all electrical power supplied to the
equipment before beginning installation.
*Blindness can occur if freon contacts your eyes.
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!CAUTION
*Do not install on any electrical system over 30 VAC.
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!CAUTION
*All electrical wiring should comply with codes and
ordinances.
Recommended Settings
At Outside Temperatures Recommended Setting
-20°F -30°C 15% (Low)
-10°F -25°C 20% (Low)
0°F -20°C 25% (Med)
+10°F -10°C 30% (Med)
+20°F -5°C 35% (High)
Over 20°F Over 0°C 40% (High)
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!WARNING:
Adjusting the
humidity control
higher than the rec-
ommended setting
may cause conden-
sation resulting in
possible damage to
the home.
WIRING INSTRUCTIONS
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!CAUTION:
*Use the wiring diagram shown for single-speed blower operation
only.
*When wiring multi-speed blower systems use an A50 relay or a fan
sail switch to prevent premature component failure.
*Consult the instructions included with the humidifier and any
additional controls for instructions on wiring.
*Fatal electrocution is possible if you contact a live wire.
*Electrical power can cause electrical shock.
*Disconnect all electrical power supplied to the equipment before
beginning installation.
*All electrical wiring must comply with codes and ordinances.
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!Caution: When wiring a
Model HFT2900FP or a
Steam Humidifier Consult
the Units wiring diagram.
These Units Don’t require
an additional transformer.
OPERATIONS CHECK
1Turn the heating system thermostat up and wait until the system
blower activates.
2Turn the humidistat clockwise to the on position; visually check
humidifier for operation.
3Turn the humidistat counterclockwise to 10% or lower; visually
check to see that humidifier shuts off.
Note: The set point where the humidistat turns on and off may not
represent the actual indoor relative humidity, due to storage and
transport environments. Allow at least 24 hours for humidity control
to adjust to the installation.
4Turn the humidistat to the recommended setting for operation (see
the recommended settings chart on page 1).
5Turn the system thermostat back to normal operation.
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!WARNING: Adjusting the humidity control higher than the
recommended setting may cause condensation resulting in possible
damage to the home.
HBP Rev. 10/02 PN/000-0756-312
Figure 3: Wiring Diagram

RETURN AIR DUCT INSTALLATION
1Locate the humidistat in the return air duct at least 12 in. up stream
prior to the humidifier or the humidifier by-pass tube.
2Remove the backing and adhere the humidistat mounting template
in a horizontal position, make sure it is level.
3Drill four 7/64 in. mounting holes.
4Drill 1/2 in. hole in the center of the template and use tin snips to
cut the rectangular hole designated by the dotted lines then remove
template.
5Remove the backing and adhere the gasket over the opening area.
6Connect the low voltage wires to the humidistat terminals. Tuck the
wire into the recessed area on the back of the base plate.
7Use sheet metal screws to securely fasten the humidistat to the
return air duct.
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!CAUTION:
*Mount the humidistat in the return air duct only,
installation on the warm air duct will destroy humidistat
element.
*Make certain the wires stay in the slot under the
mounting base.
WALL MOUNT INSTALLATION
1Locate the humidistat about 5 ft. above the floor, on an inside wall,
away from discharge registers. Also, avoid areas with extreme
variation in relative humidity levels; i.e. bathrooms and kitchens.
When wall mounting, homeowners usually prefer the humidistat
mounted beside, or in the vicinity of the heating thermostat.
2For conversion to a wall mount configuration, simply pull the
indicator knob off and remove the mounting screws, and rotate
the control 180° and reattach the mounting base Fig 2.
3Drill a 3/8 in. hole in the indention on the mounting base plate.
4Place the base assembly in the predetermined location on the wall,
in a horizontal position, make sure it is level. Mark and drill a 3/8
in. hole in the wall.
5Run low voltage wire to the location and pull about 6 in. of wire
through the hole.
6Plug the hole with nonflammable insulation to prevent drafts from
affecting the humidistat operation.
7Position the base assembly over the wire and pull the wire through
the hole previously drilled in the plate.
8Use four 1 in. screws to secure the mounting base plate to the wall.
9Connect the wires to the terminals on the control.
10 Use one 3/8 in. screw to secure the humidistat cover.
11 Remove the backing and adhere the cover label to the recessed area
on the front of the cover.
12 Push the indicator knob onto the control shaft.
Figure 1: Wiring Diagram
Figure 2: Wall Mounting Diagram
3/8 In. Screw
Humidistat
1 In. Screws
Mounting base 3/8 in. Screws
Drill 3/8 in. hole
for wires
Wire terminals
Humidistat cover
Cover label
Knob