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desired value within the range of 0 F to 76 F [0 C to 42 C].
A setback in discharge water temperature of 4 degrees is
approximately equivalent to a setback of 1 degree in
space temperature. To obtain a 10-degree setback in
space temperature, the setback knob should be set to 40
F [22 C].
MOTOR SPEED AND BOILER
DIFFERENTIAL ADJUSTMENTS
(Fig. 20)
(4CT0 16C)
ei 049
FIG. 20—W964F PANEL, REAR VIEW.
applications, the mode selector must be turned to the
on-off mode (fully counterclockwise
position).
A
l\ JUMPER TERMINALS D AND B.
FIG. 21—W964F SUBBASE.
ON-OFF CONTROL OF BURNER
A. Set mode selector to ON-OFF mode (counter¬
clockwise
position).
B. Set boiler water differential to desired value within 7 F
to 30 F [4 C to 16 C] range. An initial differential setting
of 10 F [5.5 C] is recommended as the number of
degrees through which the discharge water must
pass between relay make and break.
C. Select line or low voltage input to motor. The subbase
is shipped with jumper in low voltage position (jumper
between terminals D and B). For low voltage input to
motor, verify that this jumper is in place. For line
voltage input to motor, remove jumper from D and B,
and connect jumper to L and B.
D. Connect jumper between terminals 1 and 2.
MOTOR SPEED SELECTION
In the P+l mode, the motor speed selector screw
provides timing either for 4-minute motors (fully
clockwise
) or for 1 -minute motors (fully counter¬
clockwise
). Determine timing from the motor label.
BOILER WATER
DIFFERENTIAL SELECTION
When Aquatrol is used in on-off system applications,
set the boiler water differential screw to the required
differential—within the range of 7 F to 30 F [4 C to 16 C].
An initial differential setting of 10 F [5.5 C] is recom¬
mended.
MODE SELECTION
(Figs. 20, 21)
The Aquatrol is shipped with the mode selector screw
set in the proportional plus integral mode (fully
clockwise
position) to control a motorized 3-way
mixing valve. When aquatrol is used in on-off system
P+l MODE
(For 3-way mixing valve control)
PROPORTIONAL PLUS INTEGRAL
(P+l) CONTROL
Proportional control is corrective valve action that is in
proportion to the error or deviation of the controlled
medium temperature from set point temperature.
Proportional plus integral control moves the valve at a
speed proportional to the error or deviation of controlled
medium temperature from set point temperature. That is,
the valve is moved faster as the error gets larger. This
eliminates the offset error due to load changes.
A. Set mode selector to P+l mode (clockwise
position).
B. Set motor speed selector to desired time (1 or 4
minutes).
C. Verify that no jumper is connected between terminals
1 and 2.
11
63
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2036-4
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