TP970-TP973 PNEUMATIC THERMOSTATS
THROTTLING RANGE
SCALE (2)
(DAY/SUMMER)
THROTTLING
PLATE (2)
THERMOMETER
CALIBRATION
BOBBIN
SCALEPLATE
SETPOINT
60
INDICATOR
CALIBRATION
SCREW
(DAY/SUMMER)
STOPS
TEMPERATURE
SETTING
DAY/AUTO LEVER
(TP971 ONLY)
NOTE: NOT ALL ADJUSTMENTS ARE ON ALL THERMOSTATS.
Fig. 3. Installing TP970-TP973 without wall box.
ADJUSTMENTS
After installation, set the thermostat to the desired setpoint
and let the system operate long enough to stabilize. The
length of time required for stabilization depends on system
response time. This could be only a few minutes or as long
as several hours. Make certain that the system has
stabilized before checking calibration. If the temperature
stabilizes within one-half of the throttling range of the
setpoint, no calibration is required.
NOTE: All thermostats are accurately factory calibrated
and should require only a calibration (bleed-off)
check to ensure correct operation.
95-7478EF
GAGE TAP
ANTIHUM
SPRING (2)
THROTTLING
RANGE
ADJUSTMENT (2)
(NITE/WINTER)
TEMPERATURE
70
80
90
INDICATOR
SETPOINT
INDICATOR
(NITE/WINTER)
SETPOINT DIAL
(NITE/WINTER)
SETPOINT INDICATOR
ADJUSTMENT
Throttling Range
Throttling ranges (TR) are factory set at 4F (2K) and
should not require any change under normal
operating conditions.
If a change in throttling range is necessary, reset the
throttling range to the values specified on the job drawings.
Use the following procedures:
1. Remove stat cover and install 0 to 30 psi (0 to 207
kPa) gage in gage tap (Fig. 4)
2. Slide the TR indicator to the desired position on the
TR scale.
3. Mechanically check the TR by moving setpoint lever
to determine the difference in setpoint indication
when the branchline pressure reads 3 psi (21 kPa)
and 13 psi (91 kPa). (It may be necessary to turn the
calibration screw to adjust TR into the stat range.)
4. Reset TR to within ±2F (±1K) of required setting for
accurate control.
C3946-3
5. Follow RECALIBRATION procedures.
HOLLOW
WALL
1 INCH
HOLE
5/32 INCH
TUBING
Fig. 4. TP971 and TP972A2218 controls and indicators.
2
1-1/8
2-1/4
BACKPLATE
STAT
6 0
COVER
Front view—cover off.
9 0
8 0
7 0
C6398-1