Honeywell TP974A User Manual

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TP970 AND TP9600 SERIES PNEUMATIC THERMOSTATS
11
75-7134—1
TP979A-E
The TP979 thermostats provide independent control of
heating and cooling with dual thermostats and separate
setpoints and branch lines. This enables ZEB operation
without selected actuator springs or ratio relays (Fig. 12).
64F
66F
68F
70F
72F
74F
76F
78F
18C
20C
22C
24C
26C
ZERO
ENERGY
BAND
VALVE CLOSED
HEATING
SETPOINT
COOLING
SETPOINT
VALVE OPEN
TP979C
COOLING VALVE
PNEUMATIC
OPERATOR WITH
4 TO 11 PSI
(28 to 76 kPa)
SPRING RANGE
HEATING VALVE
PNEUMATIC
OPERATOR WITH
4 TO 11 PSI
(28 to 76 kPa)
SPRING RANGE
N.O.
N.O.
H  C
M
DA
RA
C3546
Fig. 12. TP979 Typical Operation.
The TP979D and E models provide automatic night setback
of setpoint for heating and setup for cooling. Figure 13 shows
potential energy savings with night setback operation.
VALVE CLOSED
NIGHT
HEATING
SETPOINT
DAY
COOLING
SETPOINT
VALVE OPEN
64F
66F
68F
70F
60F
62F
18C
20C
22C
16C
6  DEGREES F
(3.3 DEGREES C)
NIGHT SETBACK
NIGHT SETBACK
ENERGY SAVINGS
C3547
Fig. 13. Night Setback Operation, TP979.
Covers
Both metal and plastic covers are available offering a wide
selection of windows. See Tables 11 and 12 in the
ACCESSORIES section for more information.
MAINTENANCE
General
See Figure 14 for tools necessary to calibrate TP970 and
TP9600 Series thermostats.
Fig. 14. TP970 and TP9600 Series Thermostat
Calibration Tools.
Cleaning
Remove the thermostat cover and clean or dust the
thermostat using a soft brush or air hose. In extremely dirty or
dusty environments, clean the thermostats more frequently.
DO NOT use a high pressure air hose to remove dust. Use
only a soft brush to clean the throttling plate nozzle assembly.
No lubrication is necessary.
C3929
GAGE PORT NEEDLE
DIGITAL RELATIVE
HUMIDITY INDICATOR PEN
100
120140
160
180
80
60
200
220
40
20
0
10
25
30
20
15
5
0
GAGE 
TEST THERMOMETER
THERMOSTAT TOOL