Field Controls 46256400, Manual

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PRESSURE SWITCH ADJUSTMENT
Important:
Both the CK-41 and CK-81 power vent control systems
have a pressure switch which must be properly set before the
water heater can be started. The pressure switches are set so that
the contacts will not close until properly set by the installer. Failure
to carefully follow the procedure below for setting the pressure
switch will either prevent the water heater from operating properly
of defeat the safety feature of the control which could allow a
hazardous condition to occur in the event the power venter
operates with a venting malfunction.
1. Attach the 0.25" tubing connector on the pressure tube on the
SWG venter. Connect the supplied 0.25" aluminum tubing to
the tubing connector. Route the tubing to the power venter
control box and connect the tubing to the pressure switch.
When routing the tubing, avoid kinking the tubing by bending
the tubing too sharply.
2. Follow the lighting instructions and light the pilot (millivolt
models). Turn thermostat to the highest setting and turn on
sufficient water flow to keep the burners on continually. The
power venter should start, but the main burners will not come
on until the pressure switch is adjusted.
3. Slowly rotate the pressure switch adjustment screw
counterclockwise until the contacts close and the burners fire,
then rotate the screw 1/4 turn counterclockwise. (See Figure
15) Cycle the thermostat a couple of times to insure proper
operation.
4. Follow the "General Installation Inspection " below to make
sure the pressure switch and venting system operates properly
with all gas appliances and exhaust fans operating.
GENERAL INSTALLATION INSPECTION
Recommended procedures for safety inspection of an appliance in accordance
with the National Fuel Gas Code A.N.S.I.Z223.1. The following procedure will
help evaluate the venting system. It is intended as a guide to aid in determining
that the venting system is properly installed and is in a safe condition for
continuous use. This procedure should be recognized as a generalized
procedure which cannot anticipate all situations. Accordingly, in some cases,
deviation from this procedure may be necessary to determine safe operation of
the equipment. If it is determined that a condition exists which could result in
unsafe operation, the appliance should be shut off and the owner advised of the
unsafe condition. Corrections must be made before the appliance is put into
continuous operation. The following steps should be followed in making a safety
inspection.
1. Visually inspect the venting system for proper size and determine that there is no flue gas spillage, blockage, re-
striction, leakage, corrosion, or other deficiency which could cause an unsafe operation.
2. Insofar as practical, close all building doors, fireplace dampers, windows, and all doors in area in which the appliance
is located. Turn on clothes dryers, any exhaust fans, such as range hoods and bathroom exhausters so they operate
at maximum speed. Do not operate a summer exhaust fan. If, after completing Steps 3 through 6 it is believed
sufficient combustion air is not available, refer to the National Fuel Gas Code A.N.S.I.Z223.1, or any applicable local
codes for guidance.
3. Place in operation the appliance being inspected. Follow the lighting instructions and adjust thermostat so appliance
will operate continuously.
4. Determine that the pilot or burner is operating properly and that the main burner ignition operates satisfactorily, by
interrupting and re-establishing the electrical power of the appliance in any convenient manner. Test the pilot or
burner safety device to determine if it is operating properly by extinguishing the pilot or disconnecting the flame safety
circuit and pressure switch sensing tube from the pressure switch.
5. Visually determine that the main burner is burning properly; i.e., no floating, lifting, or flashbacks.
Figure 14
Figure 15
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