MODELS:
T498A
makes heating circuit on temperature fall.
With setting knob on extreme anti-clockwise position provides
single line break
SPST (see Fig. 2)
T498B
makes heating circuit on temperature fall.
With setting knob at OFF ( ) position provides double line
break for fuse protected 240V heating circuits (see Fig. 3).
Remakes circuit no higher than
35°C in off position. Both
models available with a thermometer located in the cover to
indicate the actual room temperature.
SETTING RANGE:
Celsius Models: 5°C to 25°C, markings every 2.5°C.
Fahrenheit Models: 40°F to 80°F, markings every 5°F.
TYPE OF SWITCHING:
Fully enclosed snap acting MICRO SWITCH .
T498A
Single line break (SPST)
T498B
SPST with double line break
(DPST in off position)
TM
WIRING CONNECTIONS:
150 mm (6 inch) stranded copper leadwires suitable for
connecting to aluminum wiring if approved special service
CO/ ALR connectors are used. Color coded BLACK to L1
(T498A,B), RED to L2 (T498B only).
ELECTRICAL RATING:
Non-inductive (resistive) rating.
22A non- inductive at 120/208/240 Vac.
19A non- inductive at 277 Vac.
CSA PERFORMANCE CERTIFICATION:
16A at 208/240 Vac.
SETPOINT ADJUSTMENT:
Control knob on face of thermostat.
SENSING ELEMENT:
Flat bimetallic blade.
DIFFERENTIAL:
Approximately 3°F [2°C] non-adjustable.
DIMENSIONS:
See Fig. 1
Nominal dimensions.
THERMOMETER:
Optional coil bimetal lO°C - 30°C [50°F - 90°F].
MOUNTING MEANS:
Direct mounting on NEMA standard vertical 2 x 4 inch
switch box, or 4 x 4 inch box with mud ring adaptor (not
provided) using 6-32 slotted Robertson
screws.
APPROVAL:
Underwriters Laboratories listed File No. E47434
Guide No. XAPX
CSA File # LR1322
TM
ACCESSORIES (not included):
272804. Range stop and cover locking assembly.
Permits field selection of minimum and maximum temperature
settings. Includes range stop assembly, cover locking screws
and wrenches.
272805C
Replacement cover assembly
for T498A Celsius white models.
272805H
Replacement cover assembly
for T498B Fahrenheit beige models.
Fig. 1
Nominal dimensions in mm (inches in brackets).
Installation
WARNING
Specifications
T498A, B Electric Heat Thermostat
SPECIFICATIONS
INSTALLATION
This thermostat is a line voltage (120-277 volt) control.
Do not install this thermostat if you are not completely familiar
and competent with electrical wiring. If improperly handled,
there can be risk of 120-277 volt electric shock hazard which may
cause serious injury or death.
LOCATION:
Install a vertical switch box for mounting the T498, 1.5 m
[4 to 5 feet] above the floor on an inside wall where the
thermostat will be subjected to average room temperature.
The thermostat should be placed away from concealed
warm or cold water pipes, warm air ducts, light switches and
dimmers, refrigerators or drafts from hallways, fireplaces,
stairways or fans. When replacing an old line voltage electric
heating thermostat, remove the old thermostat carefully to
avoid damaging the insulation on the wiring.
Check the old insulation for cracks, nicks, or fraying and apply
approved electrical tape where necessary to achieve adequate
insulation or, replace the wires in an approved fashion.
1. Leave cover on the thermostat while making connections.
2. Push the leadwires into the outlet box and insert the
thermostat into the box for mounting by pushing against
the cover.
3. Remove the thermostat cover by grasping the top and bottom
and pulling outward.
4. Turn the dial so that the set point indicator is at the 12
o' clock position. This will prevent accidental damage to
the dial stop during mounting.
5. Using screwdriver, secure the thermostat to the box by
tightening the two mounting screws. Handle thermostat with
care, excessive pressure may damage the control knob or
sensing element.
2
74 (2-29/32)
115 (4-17/32)
32 (1-1/4)
26 (1-1/32)
17 (21/32)
83 (3-9/32)
13 (½)
53
(2-3/32)
21
(53/64)
