1. 1950s
   1960s
2. 1970s

Home automatic icemakers became available during the 1960s.

1. from your home's plumbing line
   manually filled
2. from a reservoir in the refrigerator

The home automatic icemaker is hooked up to the plumbing line in your house.

1. by the electrical circuit that powers the refrigerator
   by a battery operated power source
2. by an electrical circuit separate from the refrigerator

The icemaker is hooked up to the electrical circuit that powers the refrigerator.

1. five seconds
   seven seconds
2. nine seconds

It should take about seven seconds for water to fill the ice molds.

1. freezing unit in the refrigerator
   freezing unit in the icemaker
2. cooling unit in the refrigerator

The cooling unit in the refrigerator freezes the water into ice.

1. to warm the bottom of the ice mold
   to defrost the refrigerator
2. to prevent frost

The icemaker heating coil warms the bottom of the ice mold to loosen the cubes, so the ice will fall out of the mold.

1. The cubes are frozen together.
   The mold has a feature which causes each cube to connect to the next.
2. The cubes are ejected as a single unit.

The ice cube molds are designed so each cube will connect to the next.

1. The icemaker will stop making ice.
   The icemaker will continue to make ice.
2. The refrigerator will not freeze the water.

If the shut-off arm does not return to its lowest resting position then the ice making cycle will stop.

1. water frozen slowly
   water frozen in layers
2. water frozen all at once

When water is frozen in layers the ice forms clear.

1. water frozen in layers
   water frozen all at once
2. unpurified water

Home icemakers freeze water all at once, creating cloudy ice.

1. They are the same.
   The flake machine has an ice crusher.
2. The flake machine uses a different ice mold.

The basic principles are the same, but the flake machine has an ice crusher to create ice flakes.

1. crusher mechanism
   mold size
2. accumulator

The crusher mechanism determines the size of the flake.

1. harvesting system
   refrigeration system
2. warming system

The harvesting system ejects the ice.

1. for restaurant use
   for home use
2. to pack perishable items

Ice flakes may be used to pack perishable items.

1. standard shape and size
   ice flakes
2. cloudy cubes

Most restaurants and hotels prefer cubes with a standard shape and size.

1. to push the ice cube tray
   to freeze the cubes
2. to shape the cubes

Some commercial icemakers have cylinder piston that gives the ice cube tray a push, forcing the cubes into the collection bin.

1. A thermostat monitors the water in the molds.
   A timer is set for a pre-selected time.
2. There is a built-in sensor.

An icemaker has a built-in thermostat to monitor the water temperature of the molds.

1. A thermostat is used to monitor temperature.
   A predetermined time is set.
2. There is a built-in sensor.

A commercial ice machine has a time setting for the water to freeze.

1. metal
   plastic
2. rubber

Home icemaker molds are made of plastic.

1. late 19th century
   early 20th century
2. mid-20th century

During the early 20th century, home refrigeration became available.