V4062A,B,D HI-LO-OFF FLUID POWER GAS VALVE ACTUATOR
7
60-2099—9
ADJUSTMENTS
Low-Fire Adjustment
The low-fire position is adjustable from 0.16 in. to 0.64 in.
(with respect to V5055/V5097B Valve) valve stem travel. A
dial on the low-fire cam (Fig. 6) indicates the low-fire setting.
Because the cam rotates as the valve opens, scales are
marked on the dial so the low-fire setting can be observed
with the valve in any position. One scale is visible when the
actuator is closed, and the other is visible when it is open.
These scales are not independent; the same setting applies to
both. The low-fire setting is adjusted either before the actuator
is installed or after the entire system is operational. Refer to
form 70-8311 for valve flow (capacity) curves.
IMPORTANT:
When using the V4062 with a V5055/V5097C or E
Valve (with double seal), match low-fire minimum
position to burner and application. Too low a position
could result in loss of burner flame. This low-fire
position should also be checked at periodic
maintenance intervals.
For most effective use of the V4062/V5055 or V4062/V5097,
be sure to select a valve body size closely corresponding to
burner capacity. An oversized valve might not allow the
low-fire rate to be adjusted to the desired minimum setting.
The V4062 Actuator is shipped from the factory with the
low-fire setting at MAX to provide a valve gas flow of
approximately 50 to 60 percent, which is adequate for safe
lightoff until the final setting can be determined.
Fig. 6. Low-fire position can be adjusted from 0.16 in. to
0.64 in. (with respect to V5055/V5097B) valve stem travel.
Recommended Procedure
To adjust the low-fire setting without energizing the actuator,
proceed as follows:
1.
Remove the wiring compartment cover.
2.
Manually rotate the cam and dial assembly downward
so that the setscrew is accessible from the front of the
actuator.
3.
Loosen the setscrew on the low-fire cam using the
special wrench (supplied—taped to the inside of the
actuator cover).
4.
Set the cam to the predetermined low-fire setting for the
burner being used.
5.
Tighten the setscrew in the cam.
6.
Replace the wiring compartment cover.
Alternate Procedure
To adjust the low-fire setting after the burner is in operation,
use the following instructions:
1.
Remove the wiring compartment cover.
2.
Check to be sure the low-fire adjustment is set at MAX
to assure a safe lightoff. (Low-fire adjustment is preset
at the factory in the MAX position.)
3.
Disconnect the firing rate controller leadwire from
terminal 4 on the actuator to keep the valve in the
low-fire position (Fig. 4).
4.
Start the system and establish the main burner flame.
5.
Loosen the setscrew in the cam (Fig. 5) with the special
wrench. Keep the wrench seated in the setscrew.
Rotate the cam slightly downward (by moving the
wrench toward the actuator base) to open the bleed
valve. The actuator will start to close.
6.
When the valve reaches the desired low-fire position,
quickly tighten the setscrew and remove the wrench.
If the desired low-fire setting is missed, loosen the
setscrew and rotate the cam in the opposite direction to
the desired setpoint.
7.
Shut down the burner, and then restart. Repeat several
times to be sure the low-fire setting is suitable for
correct burner lightoff. Readjust, if necessary.
8.
Disconnect power and reconnect the controller leadwire
removed in step 3.
9.
Replace the wiring compartment cover.
Adjust Auxiliary Switch (If Used)
The auxiliary switch can be adjusted to operate at any point in
the actuator stroke. After installing the switch in the actuator,
turn the adjustment screw (Fig. 2) clockwise
to cause
the switch to operate earlier in the stroke or turn
counterclockwise
to cause the switch to operate later
in the stroke.
NOTE: The proof-of-closure switch is not adjustable.
Adjust Max Flow Limit Switch (Fig. 2)
The Max Flow Limit Switch is adjustable throughout the
actuator stroke. With the switch installed in the actuator, turn
the adjusting screw clockwise
to cause the switch to
operate earlier in the stroke (less flow) or counterclockwise
to cause the switch to operate later in the stroke
(more flow).
MAX
MAX
E
LOW-
FIRE
CAM
MIN
D
C
B
A
LO FIRE
SETSCREW
DUAL
LOW-FIRE
SETPOINT
INDICATORS
(SHOWN AT
MAX WITH
VALVE OPEN)
DIAL
M7340