Dual Level Control Auto Refill And Low Water Cutoff System

1.Dual Level Control: What it does:

A.AUTO REFILL of the water compartment to keep the tank filled with water. When water is used, the fill valve opens automatically to let more in. The fill valve closes when the water level reaches full.

B.LOW WATER CUTOFF to prevent burn out of the electric immersion heater when there is not enough water to cover it. When low water occurs, the heat automati- cally switches off. The heat stays off until more water is added.

C.A device called a DUAL LEVEL CONTROL keeps the tank filled with water and turns off the heat when water is low by simultaneously monitoring two different water levels.

2.Description and Operation of the Dual Level Control System:

A.Components

1.Dual Level Control - switches power to both the thermostat and water inlet solenoid valve by sensing changes in water level.

Fill Heat

H N

 

120 VAC

Transformer

Relays

Probes

HI XL C

Printed Circuit

2.Electrode Assembly - consists of a high (short) and a low (extra long) sensing electrode, or probe, molded in an epoxy body.

Red Wire

Green Wire

Green Wire

HighLow

High

Red Wire

Low

Top Mounted Probes

Side Mounted Probes

3.Metal Enclosure (tank body)- provides a common (ground) connection for the electrode circuit.

 

 

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American Metal Ware 87710E Coffee Urn

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Grindmaster 87710 service manual Dual Level Control Auto Refill And Low Water Cutoff System