
NOTES:
The Thermostats are accurately factory calibrated and
should require only the
CHECK
to
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.
BRANCH LINE
IF THERE IS NO ANTIHUM SPRING OR CONE, THERE IS
AN ADHESIVE PAPER DOT ON THE THROTTLING PLATE
3907-4
off
showin
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])
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
CAIBRATION
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 e
within
degree F (0.56 degree
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 Thermostat to the desired setpoint and allow Set the throttling range to the value specified on the
ob drawing.
the system to stabilize before proceeding.
13
95-7135