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RED
Y
WHITE
R
W
BLUE
THREE-WIRE SPDT
T87F
VALVE OR MOTOR
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
Fig. 6. T87F used for series 203-wire, spst control of
low-voltage motors and electric radiator valves. Used
in applications where thermostat makes contact on
both rise and fall in room temperature.
THERMOSTAT WALLPLATE
OR SUBBASE
Y
R
COOLING
2
CONTACTOR COIL
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND
OVERLOAD PROTECTION AS REQUIRED.
2
ONLY R AND Y TERMINALS ARE USED FOR COOLING ONLY.
Fig. 7. T87F used in cooling only system.
Mounting Thermostat to Wallplate or Subbase
To remove standard cover, pull ring outward with
fingertips, pressing lightly on dial with thumbs.
To remove locking cover, loosen the three screws along
the cover edge with the Allen wrench supplied. Remove
the cover as indicated above.
Remove and discard the plastic insert protecting the
mercury switch.
Align the thermostat over the wallplate and tighten the
three captive mounting screws. These captive screws
complete the electrical connections to the thermostat.
Adjust heat anticipator to match current rating of primary
control. See Fig. 8.
Heat Anticipator Setting
If the T87F is used for 3-wire, spdt, heating-only (series
20) control (Fig. 6), set the heat anticipator for 1.2 (far left
end of scale). A fixed resistor type heater is provided in
the 137421A or 198170A Wallplate for this application.
For other control applications, proceed as follows.
Adjust anticipator to match current rating of primary
control. Rating is usually stamped on the control
nameplate. Move the indicator to the marking that
matches this rating. Indicator may be moved with fingers
or pencil point through hole shown in Fig. 8. If the current
rating is not given, proceed as follows before mounting
the thermostat:
1. Connect an ac ammeter of appropriate range (0 to
2.0A, for example) between the R and W terminals
on the wallplate or subbase.
2. 2.Let the system operate for one minute before
reading the ammeter.
3. Move the anticipator indicator to match the amme-
ter reading.
L1
(HOT)
R
TR
L2
W
B
M5319
L1
(HOT)
1
NOTE: A slightly higher setting to obtain longer burner-
on times (fewer cycles per hour) may be desir-
able for some systems.
1
RECALIBRATION
The T87F is calibrated at the factory; recalibration should
not be necessary. If the thermostat is accurately leveled
but continues to be out of calibration, order 104994A
Calibration Wrench. Instructions for recalibrating are
included with wrench.
L2
SCALE
HOLE SUITABLE FOR
PENCIL POINT
TO MOVE INDICATOR
M3516
Fig. 8. Setting heat anticipator current rating.
CHECKOUT
Heating
1. Turn down temperature setting to lowest point. If
subbase or remote switching is used, move
System switch to Heat position.
2.
Raise temperature setting until heating equipment
starts.
3. Lower temperature setting below room tempera-
ture and heating system should shut down.
4. Make certain all equipment responds properly to
the thermostat.
5. Heating equipment should stop when dial is turned
below room temperature.
Cooling
CAUTION
Equipment Damage Hazard.
Operating cooling equipment within
guidelines can prevent compressor damage.
Do not operate cooling when outdoor
temperature is below 10°C (50°F).
Allow five-minute off-time after compressor has
run before restarting.
1. If T87F controls cooling, move System switch (if
used) to Cool postition.
2. Lower temperature setting until cooling equipment
starts.
3.
Raise setting above room temperature and cooling
system should shut down.
4. Make certain all equipment responds properly to
the thermostat.
3
T87F UNIVERSAL THERMOSTAT
.12
.15
HEAT
ANTICIPATOR
INDICATOR
M1368A
95-6731—6
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