Thermostat Installation - Williams 2509622 Owner's Manual

Installing Your Furnace

Thermostat Installation

Williams' furnaces are operated by a millivolt type thermostat.
Current to the thermostat is supplied by the pilot generator. Do
not connect it to electricity. Anticipator settings are not required.
Use of existing wire is acceptable if it is in a satisfactory
1.
location and the wire is in good condition. When in doubt,
use new wiring.
If a new location is chosen or if this is a new installation,
2.
thermostat wire must first be run to the location selected.
All wiring must agree with local codes and ordinances.
These instructions cover bringing the wire down from the
attic but it may be run from a basement or crawl space
using similar methods.
Before drilling a hole in the wall at the selected location,
3.
drive a small finish nail through the ceiling in the corner of
the wall and ceiling above the thermostat location. Pull the
nail out and push a small, stiff wire through the hole so it
can be found in the attic. Drill a ½-inch hole through the
ceiling wall plate.
Probe for obstructions in the partition. Then, drill a ½-inch
4.
hole through the wall at the selected location for the
thermostat.
From the attic, feed the thermostat wire through the wall
5.
until even with the thermostat location.
Snag the thermostat wire through the hole and pull the wire
6.
through the hole in the wall so that 6-inches of the wire
protrude.
Route wires to the furnace.
7.
Never use nails or staples across the thermostat wires.
8.
CAUTION: Label all wires prior to disconnection
when servicing controls. Wiring errors can cause
improper and dangerous operation. Verify proper
operation after servicing. Refer to installation
instructions packed in the thermostat carton if you
have any doubt about the above procedures.
WALL-MOUNTED THERMOSTAT INSTALLATION
To remove the thermostat cover, squeeze both sides and lift.
1.
Connect the thermostat wires to the terminal screws on the
2.
base of thermostat.
Push any excess wire back through hole in the wall and
3.
plug hole with insulation to prevent drafts from affecting
thermostat operation.
Be sure to level the thermostat for best appearance. Fasten
4.
thermostat base to the wall through mounting holes with
screws provided.
Replace the thermostat cover.
5.
Do not run wire in any location where it might be damaged.
6.
Avoid splicing the thermostat wires unless the spliced wires
are properly cleaned, soldered and taped.
Use the 18-gauge wire as supplied for a maximum length of
7.
20-feet. If a longer length is needed, use 16-gauge wire to
a maximum length of 25-feet.
Connect the thermostat wires to the control valve as shown
8.
in Figure 17.
FIGURE 17 – Thermostat Wiring
FACE PANEL-MOUNTED THERMOSTAT INSTALLATION
Before removing the face panel, disconnect the thermostat
1.
wires at the gas valve.
Locate the knockout on the right side of the furnace to
2.
mount the thermostat. Remove the knockout by tapping it
lightly with a screwdriver (Figure 18).
necessary to cut a 1/2-inch hole in the inside panel
insulation for clearance to the knockout.
Cut the thermostat wire to 56 inches.
3.
Connect the thermostat wires to terminal screws on the
4.
thermostat base.
Feed the thermostat wires through the knockout and route
5.
them through the metal clip to the gas valve.
Mount the thermostat to the side of the cabinet with screws
6.
provided.
Replace the thermostat cover.
7.
Connect the thermostat wires to the control valve as shown
8.
in Figure 17.
FIGURE 18 Knockout Holes
IMPORTANT: Keep the thermostat wires away from the
combustion chamber.
It will also be