SETTINGS AND CHECKOUT
Move the temperature setting lever to the desired
setpoint on the thermostat scaleplate. See Fig. 1.
Temperature is controlled to that point. On positive Off
models, the control circuit is broken when the lever is
moved to the extreme lowest end setting of the
Heat Anticipator Setting (T810D)
1. Use this thermostat only with controls that have
current rating equal to (or within) the rating of
the heat anticipator.
2. The T810D Thermostat is equipped with an
adjustable heat anticipator and operates cor-
rectly only if this heater is adjusted to match the
current draw of the primary valve or relay.
3. Do not use the T810 Thermostat on Powerpile®
(millivolt) Systems. Use the TS810 THermostat
that is designed for use on the Powerpile®
The T810D features an adjustable heat anticipator rated
from 0.18A to 0.8A at 30 Vac. This heat anticipator must
be adjusted to match the current draw of the primary
control for optimum thermostat performance. The rating
of the primary control is stamped on the control
nameplate. To adjust, move the anticipator indicator lever
to correspond to the control rating.
If the setting and current rating are not available, wire the
thermostat into the system, but do not attach it to the
wall. If the thermostat is already mounted, remove it from
the wall, leaving it connected to the system wiring.
Connect an ammeter of the appropriate range (about
0.0A to 2.0A) between the terminals on the back of the
thermostat. Move the temperature setting lever to a low
setting so the contacts are broken. In cold weather, it
may be necessary to hold the switch so the controls
remain open. Allow the system to operate through the
ammeter for one minute. Adjust the anticipator to match
the meter reading.
T810D; TS810B HEATING THERMOSTATS
NOTE: For best performance, the heat anticipator can
require further adjustment. To lengthen burner-
on time, move the indicator in the direction of
the longer arrows, but no more than one-half
scale marking at a time. To shorten burner-on
time, move the indicator in the opposite direc-
Equipment Damage Hazard.
Shorting across system controls can damage
Do not short across system control terminals to
check system operation.
To assure accurate temperature control, do not
touch or breathe on bimetal of thermometer.
1. Observe the system through at least one complete
2. Be sure the system operates as intended.
3. Check for correct operation of the positive Off
switch, if used
This thermostat is carefully calibrated at the factory and
should not need field adjustment. If the thermostat seems
out of adjustment, check as follows:
1. Move the temperature setting lever to the lowest
end setting of the temperature scale. Do not move
the lever all the way to Off on models with positive
Off switch. Wait at least five minutes.
2. Remove the thermostat cover. Slowly move the
temperature lever until the snap switch just makes
3. Replace the cover and wait five minutes for the
cover and the thermostat to lose the heat gained
from your hands. If the thermometer pointer and
the setting lever indicator read approximately the
same, no recalibration is needed.
If the thermostat needs recalibration, order part no.
104994A Open-end Wrench. Follow the recalibration
instructions included with the wrench.