Burnham K50 Minimum Input Adjustments, V8944B Combination Valve, Motorized Modulating Actuator

(1)

With power to actuator “off”, remove the

wiring compartment cover.

(2)

Check to be sure the low fire adjustment is set

at MAX to insure a safe light-off. (Low fire

adjustment is preset at factory in the MAX

position.)

(3)

Disconnect the controller lead from terminal #4

on the actuator to keep the valve in the low fire

position.

(4)

Start the system and establish the main burner

flame.

(5)

Loosen the setscrew in the cam (Fig. 58A) with

the special wrench taped to inside of actuator

cover. Keep the wrench seated in the setscrew.

Rotate the cam slightly downward (by moving

the wrench toward the base of actuator) to open

bleed valve. Actuator will start to close.

(6)

When valve reaches desired low fire position,

quickly tighten setscrew and remove wrench. If

the desire low fire setting is “missed”, merely

loosen the setscrew and rotate cam in the

opposite direction to the desired set point.

(7)

Shut down burner, and then restart. Repeat

several times to be sure the low fire setting

is that desired and suitable for correct burner

lightoff. Readjust if necessary.

(8)

Disconnect power and reconnect controller lead

removed in step (3) above.

(9)

Replace the wiring compartment cover.

c. MINIMUM INPUT ADJUSTMENTS –

MOTORIZED “MODULATING” ACTUATOR,

V9055A

On boilers equipped with Fluid Power Valves that

have “Modulating” Actuators, Low Fire Adjustment

should not be less than Minimum Input shown on

Rating Plate (1/3 of full rated input).

Fig. 58B shows the Low Fire Adjusting Screw

for increasing or decreasing low fire input on the

Honeywell V9055A “Modulating” Actuator. To

adjust the low fire setting after the burners are “on”,

the following procedure should be used.

(1)

With power to actuator “off”, remove the wiring

compartment cover.

(2)

Check to make sure the low fire adjustment is

set at MAX (full clockwise) to insure a safe

light-off. (Low fire adjustment is preset at the

factory in the MAX position.)

(3)

Remove the lead to V9055A terminal R.

Jumper terminal R to W. This will prevent the

actuator from going to the high fire position.

(4)

Energize the system and light the main burner.

(5)

Use a Phillips screwdriver, or standard type with

a blade no more than 3/16 inch wide, to turn

the low fire adjusting screw for the desired low

fire position. DO NOT PUSH INWARD ON

SCREW.