VHX SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS
HIGH LIMIT PRESSURE
SWITCH ADJUSTMENT
NOTE: Before the high limit pressure switch can be adjusted, the cycling pressure switch must be temporarily removed from the boiler control circuit. This allows the boiler to pressurize above the normal operating range. After the high limit pressure switch is properly adjusted, the cycling pressure switch must be returned to its normal operating condition. Follow the procedure as outlined in the steps below.
1.Access cycling pressure switch as outlined under PRESSURE SWITCH CONTROL BOX COMPONENTS in REMOVAL AND REPLACEMENT OF PARTS.
A.Remove cover from cycling pressure switch.
B.Connect a jumper wire between the two electrical terminals to temporarily remove the cycling pressure switch from the boiler control circuit.
2.Reconnect power to machine and turn power switch on (boiler begins to fill).
3.Press reset switch and verify high pressure light turns off.
4.When green ready light comes on, press reset switch to begin heating (low water light turns off).
NOTE: A pressure relief valve with a 15 PSI setting, serves as
5.Monitor boiler pressure gauge. Note pressure at which the high limit pressure switch opens (high pressure light turns on).
The switch should open at boiler pressures no less than 14.5 PSI but no greater than 15.0 PSI (MAX).
A.If pressure reading differs, continue with procedure to adjust.
CAUTION: While making the adjustment, do not press on the wheel with extreme force. The switch may rotate and develop a leak at the compression fittings or in some cases, the rear lead wire may touch the control box and create an electrical short.
6.Turn adjustment wheel to change high limit pressure switch setting.
A.A counterclockwise rotation lowers the pressure switch set point; a clockwise rotation raises the pressure switch set point.
NOTE: For every click of the adjustment wheel, the pressure setting is changed approximately 1/8 PSI.
NOTE: Make the adjustment in small increments.
7.After adjusting high limit pressure switch, the boiler pressure must be reduced to check the pressure setting.
A.Remove left side boiler base panel to access the manual ball valve on the probe housing assembly.
WARNING: THE STEAMER AND ITS PARTS ARE HOT. USE CARE WHEN OPERATING, CLEANING OR SERVICING THE STEAMER. THE BOILER CONTAINS LIVE STEAM. STAY CLEAR WHEN OPENING THE VALVE.
B.Open the manual ball valve to release boiler pressure and monitor the boiler pressure gauge.
NOTE: High limit pressure switch resets at approximately 12 PSI (not adjustable).
C.When pressure is reduced to approximately 8 PSI, close the ball valve.
D.Press reset switch to reset the high pressure safety circuit and begin heating (high pressure light turns off).
8.Monitor boiler pressure gauge and note the pressure at which the high limit pressure switch opens.
A.If pressure is correct, the high limit pressure switch is properly adjusted.
B.If pressure is not correct, repeat the adjustment for up to three attempts.
9.If the above adjustment cannot be obtained, install a replacement high limit pressure switch and adjust as outlined in this procedure.
10.After the high limit pressure switch is properly adjusted, disconnect power to machine and allow boiler to blowdown/drain.
11.Remove jumper wire from cycling pressure switch to return the switch to its normal operating condition.
12.Check for proper operation.
BOILER FILL AND COLD WATER CONDENSER SOLENOID VALVES
1.Access boiler fill and cold water solenoid valves as outlined under PRESSURE SWITCH CONTROL BOX COMPONENTS in REMOVAL AND REPLACEMENT OF PARTS.
2.Turn power switch on (boiler begins to fill).
F25154 (February 2004) |
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