Low Water Cut-Off
This service is indicated if the distilled water in the steam jacket is at the proper level but the switch does not close to make the circuit across the two top terminal screws (the bottom two are not used), if leakage is observed from the switch case, or if the distilled water level is near the bottom of the gauge glass and the switch does not open.
To replace or to check the switch, remove the lead wires, remove the two screws and the metal cover over the switch. Remove the four flat head screws holding the switch in place, then remove the switch. To check the switch, gently press the bottom of the rocker toward the switch body; this should close the switch. Then press the rocker in the other direction; this should open the switch. When installing the switch, be sure the word "TOP" on the switch is at the top.
To replace the complete unit, remove the lead wires, remove the ten screws around the base of the metal switch cover and pull the complete unit forward. When installing the new unit, be sure the word "TOP" on the switch is at the top and that the side of the square terminal block is vertical.
Pressure Limit Switch
This service is indicated if a circuit check shows the switch is not closed or if the switch is opening at too low a pressure. It was factory set to open at 15 p.s.i. and to close at 6 p.s.i.
To remove the switch for service, disconnect the tubing from the bottom of the unit and remove two screws with nuts which anchor the mounting bracket for the unit.
The
Magnetic Contactor
This service is indicated if a circuit check shows power at the proper voltage is supplied to the magnet coil terminals, yet the contactor fails to open or close as it should or it chatters or hums.
A chatter or a humming noise usually is the result of dirt or lint on the armature pole faces or around the armature core so that the magnet coil does not completely pull the armature into the sealed position. This can usually be corrected by blowing or wiping the pole faces clean. The pole faces are at the bottom of the contactor directly behind the magnet coil terminals.
To inspect the contactor contact points, on 70 and 125 ampere contactors, remove the grey color plastic arc shield at the top of the contactor by removing the two screws holding it in place. The 50 ampere contactor has no arc shield. For a better view or for other service, remove the two wires to the magnet coil at the coil terminals (terminals at the bottom of the contactor), remove the two screws holding the coil in place and lift the coil and armature assembly out.
Pitted contacts should be replaced. These may be obtained from
Electric Heating Elements
This service is indicated if a check with an ammeter shows the K.W. input is not proper. Proper amperage for each K.W. input is shown under ELECTRICAL CONNECTIONS in this manual.
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