Field Controls CK-63 - Adjustments and System Checks; Pressure Switch Adjustment; Post Purge Timing Adjustment; System Control Checkout

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Figure 7
Figure 8
ADJUSTMENTS
PRESSURE SWITCH ADJUSTMENTS
With the venter air  ow set and the appliance operating at
the best operating e ciency, adjust the pressure switch by
rotating the adjustment screw clockwise until the burner shuts
o , then rotate the adjustment screw counterclockwise until
the burner  res. Rotate the adjustment screw an additional
1
⁄4
to
1
⁄2 turn counterclockwise to ensure proper switch setting.
(See Figure 7)
POST PURGE TIMING ADJUSTMENT
To adjust the post purge time, rotate the
timer adjustment on the timer clockwise to
increase the operation time. To decrease the
operation time, rotate the timer adjustment
counterclockwise. (See Figure 8) Typical post
purge time should be between 3 to 5 minutes.
If running burner simultaneous with venter,
1-3 minutes is suggested.
SYSTEM CONTROL
CHECK OUT PROCEDURES
1. Adjust the thermostat to call for heat
and observe the power venting system
for proper operation sequence (repeat if
necessary).
a. Thermostat calls for heat.
b. Relay is energized and venter motor
starts.
c. Pressure switch closes and burner
starts. The LED light indicates power
to T3. When the pressure switch closes
with a call for heat, the LED light will
come on. This indicates that the burner should be in a burn cycle. (See Figure 8)
d. Thermostat is satis ed, burner stops and venter motor should operate for the set post purge time. The LED
should not be on during the post purge.
2. While system is operating, disconnect power to the venter motor. This should open the pressure switch contacts
and stop burner operation.
3. (If WMO-1 switch is installed) Allow vent system to cool. Disconnect the vent pipe between the venter inlet and
the appliance outlet. Block the vent pipe with a noncombustible material. Activate the heating system with the
main burner operating. Allow approximately 2 minutes or less for the secondary safety switch to deactivate the
burner. Reset safety switch after waiting 15 minutes for WMO-1 to cool down and repeat.
P/N 46400900 Rev P 08/19