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Calibration
General
After installation, set the thermostats to the desired setpoints
and let the system operate long enough to stabilize. Verify that
the system has stabilized before checking calibration.
are factory calibrated and should require only a
bleed-off check to verify correct operation. The throttling range
is factory set and should not require adjustment under normal
operating conditions. Figure 10 shows thermostat components.
THERMOMETER
SCALEPLATE
lNDlCATOR
CALIBRATION
DAY/AUTO LEVER
(TP971 ONLY)
NOTE: NOT ALL ADJUSTMENTS ARE ON ALL THERMOSTATS_
Fig. 10. Thermostat Front View, Cover Off.
Throttling Range Adjustment
Use Thermostat Tool to remove cover. Assemble Gage
and Gage Port Needle.
Insert Gage Port Needle in thermostat gage tap.
Slide throttling range (TR) adjustment to desired
position on TR scale.
4.
Mechanically check TR by moving setpoint indicator to
determine difference in setpoint indication when
branchline pressure reads 3 psi (21 kPa) and 13 psi
(91 kPa).
NOTE:
required, turn calibration screw to adjust TR
into thermostat range.
5.
Reset TR to within &2 degrees F (HK) of required setting.
6.
Follow applicable procedure under CALIBRATION
CHECK.
ANTlHUM
SPRING (2)
THROTTLING
RANGE
ADJUSTMENT (2)
(NlTE/WINTER)
TEMPERATURE
INDICATOR
SETPOINT
INDICATOR
(NlTE/WINTER)
SETPOINT DIAL
(NITE/WINTER)
ETPOINT INDICATOR
ADJUSTMENT
Calibration Check;
Direct-Acting Thermostats (TP970A,
TP971A, D)
Use Test Thermometer to measure actual temperature
of space.
Turn setpoint indicator down to 5 degrees F (2.8K)
below room temperature.
3.
Wait 5 to 10 seconds to allow thermostat to build up
branchline pressure.
4.
Turn setpoint indicator up slowly.
5.
If thermostat begins to bleed off between 1 degree F
(0.6K) and 3 degrees F (1 .7K) below room temperature,
no recalibration is necessary. If recalibration is needed,
see RECALIBRATION.
Reverse-Acting Thermostats (TP970B,
TP971B, E)
Use Test Thermometer to measure actual temperature
of space.
2.
Turn setpoint indicator up to 5 degrees F (2.8K) above
room temperature.
3.
Wait 5 to 10 seconds to allow thermostat to build up
branchline pressure.
4.
Turn setpoint indicator down slowly.
5.
If thermostat begins to bleed off between 1 degree F
(0.6K) and 3 degrees IF (1.7K) above room temperature,
no further calibration is necessary. If recalibration is
needed, see RECALIBRATION.
Recalibration
The procedures in this section assume that a calibration check
has been performed (see CALIBRATION CHECK) and that
the thermostat did not operate correctly.
NOTE: Verify that the adhesive paper dot (see Fig. 10) is in
place before beginning recalibration.
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