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CHECKOUT AND TESTING
WARNING
Do not rotate the Thermostat control shaft more than
two revolutions clockwise from the original position as
received. Rotating the shaft more than two revolutions
from the original position can cause permanent
damage to the Thermostat.
Using a CCT729A Gage Adaptor, insert a 0 to 30 psi
(0 to 207 kPa) gage into gage plug on front of
Thermostat. Turn setpoint knob above and below bulb
ambient temperature. If the branchline pressure can
Setpoint
Range in F
65-85 (18-29)
40-80 (4-27)
60-80 (16-27)
1
The LP916B1058 WARMER-COOLER model has a throttling range of 2
degrees F (1K) when on reverse-acting (9psi supply pressure).
CALIBRATION
The Thermostat is factory calibrated at midscale (pointer
vertical) and normally requires no adjustment. (Warmer-
Cooler models are calibrated at 75F.) If recalibration is
required, allow enough time (up to three minutes) for the
branch pressure to stabilize.
LP916A and C Calibration
Apply 18 psi (124 kPa) main line pressure.
Measure temperature at bulb location.
Remove setpoint knob.
Rotate control shaft to achieve 8 psi (55 kPa)
branchline pressure. Do not rotate shaft more than two
revolutions clockwise from original position as received
and allow enough time (up to three minutes) for branch
pressure to build up.
WARNING
Rotating shaft more than two revolutions clockwise
from original position can cause permanent damage
to the Thermostat.
Replace setpoint knob and position pointer to
correspond to temperature measured at remote bulb.
The center division on the scale is the middle of the
setpoint range.
(C)
Scale/Increments
1
WARMER-COOLER/0.9 degree F
40-50-60-70-80
60-80/1 degree F
LP916A-C PNEUMATIC REMOTE BULB THERMOSTATS
be varied from 0 psi (0 kPa) to full main pressure
within the rated throttling range, the Thermostat is
operating properly. If not, recalibrate (see
CALIBRATION section).
NOTE: Allow enough time for the branch pressure to
build up (up to three minutes) when checking
out this device.
The following table lists throttling range and scale increment
values for various Thermostat models:
Throttling
Range in degrees F
3.5 (2)
7 (3.5)
3.5 (2)
LP916B Calibration
For direct action, follow Steps 1 through 5 of LP916A
and C calibration.
For reverse action (except LP916B1058), apply 13 psi
(90 kPa) main line pressure. For LP916B1058, use 9
psi (62 kPa) main line pressure.
For applications requiring different control points for
heating and cooling Zero Energy Band (ZEB), reset
setpoint knob towards COOLING, one division for each
0.9 degree F (0.5 degree K) of ZEB desired.
Adjust switchover lever stop (Fig. 18) for 8 psi (55 kPa)
branchline pressure (6 psi [41 kPa] for LP916B1058).
7
(K)
95-5559
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