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NOTES:
The Thermostats are accurately factory calibrated and
should require only the
ensure correct operation"
The antihum spring (Fig. 19) must be free. Be sure the
spring just touches the throttling plate and is not
wedged against it (does not apply to all TP970C and D
or any TP970 series starting with 2000, i.e,
TP972A2-i 43).
3. The Thermostats are very sensitive and should not be
heated by excessive handling during calibration.
4. Calibration of the TP974 is not recommended.
5. To check calibration or to recalibrate the TP978 ZEB
Thermostats, measure actual room temperature with a
test thermometer. The 75F (246) limit is nonadjustable.
IF THERE IS NO ANTIHUM SPRING OR CONE, THERE IS
AN ADHESIVE PAPER DOT ON THE THROTTLING PLATE
Accurate thermometer
Pressure Gage 1400351 9-001 (0 to 30 psi [0 to 207 kPa])
Gage Adapter MQP729 (CCT729)
Thermostat Tool MQT735A (CCT735A) or 0.05 in. (3/64 in.)
hex key
Thermometer Calibration Tool MQT970 (for all models or an
1/8-in. hex wrench for series thermostats starting with
2000 [e.g., TP972A21 43])
Set the Thermostat to the desired setpoint and allow
the system to stabilize before proceeding.
CHECK to
LINE
BRANCH
3907-4
off showin
Turn the setpoint indicator adjustment down (DA) or up
(RA) until the setpoint indicator reads 5 degrees F (2.8
degrees C) below (DA) or above (RA) room
temperature. If the BLP at the Thermostat does
not build up within 30 seconds, proceed to
C A I B R A T I O N PROCEDURE.
Turn the setpoint indicator adjustment up (DA) or down
(RA) slowly. If the Thermostat does not bleed off audibly
between and 3 degrees F (0.56 and 1.7 degrees C)
below (DA) or above (RA) room temperature, proceed
to CALIBRATION PROCEDURE.
Measure the ambient temperature with an accurate
thermometer. Compare the thermometer reading with
the Thermostat thermometer reading.
If the difference is rnore than degree F (0.56 degree
C), use the Thermometer Calibration Tool or hex
wrench to turn the Thermostat thermometer calibration
bobbin (Fig. 19) until the Thermostat thermometer
reading is correct.
Ensure the main line pressure is at the
recommended setting.
All Thermostats except the TP978E: Install the Pressure
Gage with the Gage Adapter into the branchline
pressure gage tap.
TP978E: Install the Pressure Gage in the branch line
remote from the TP978E.
Turn the setpoint indicator adjustment until the setpoint
indicator reads the existing temperature.
Follow the remaining steps shown for the Thermostat
being calibrated.
Set the throttling range to the value specified on the
job drawing.
Turn the calibration screw (Fig. 19) until the Pressure
Gage reads 0 psi (0 kPa).
Turn the calibration screw in the opposite direction until
the Pressure Gag
The TP970 is now
thermometer shoul
C) of each other.
Remove the Pressure Gage and Gage Adapter.
Turn the setpoint indicator adjustment until the setpoint
indicator is at the desired setting.
Proceed to SWITCHOVER CALIBRATION
PROCEDURE.
Set the throttling range to the value specified on the
ob drawing.
1 3
e within
degree F (0.56 degree
95-7135
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