Electrolux 30" GAS FREESTANDING RANGES, Руководство по обслуживанию

Страница: 90 / 132

90
resistance of the oven sensor indicates the temperature
in the oven is about 10°F above the programmed
temperature, the microprocessor opens the relay, which
removes power from the bake circuit and closes the
safety valve. When power is removed from the bake
circuit the oven temperature begins to lower. As the
oven temperature lowers, the resistance of the oven
sensor decreases. When the oven drops to about 10
degrees below the programmed temperature, the
resistance of the sensor tells the microprocessor to
close the relay contacts, and provide power to the bake
circuit. After the first cycle the “Pre” in the display goes
out indicating the oven is preheated.
Note: 120 VAC is at the oven igniter as long as the
control calls for heat.
Bake:
When the bake pad is touched, and a temperature is
set with the up or down arrows the bake relay on the
board closes, applying line to neutral voltage across
the oven bake circuit. The bake circuit is a series circuit
made up of the electronic oven control, a silicon
carbide igniter that reduces in resistance as it heats up,
and a current sensitive oven safety valve that needs a
minimum of 3.2 amps of current to open. When electrical
power is first applied to the circuit the resistance of the
igniter is high enough that the current flow in the circuit
is below the amount needed to open the safety valve. As
electrical current flows through the igniter it causes the
silicon carbide material to heat, reducing the resistance
of the igniter and increasing the current flow in the
circuit. When the temperature of the igniter reaches
around 1800°F the current flow in the circuit exceeds 3.2
amps. The oven safety valve opens allowing gas to flow
into the bake burner. The gas is then ignited by the heat
of the bake igniter and the oven begins to heat up.
In the tip of the oven sensor is a positive coefficient
thermistor that increases in resistance as the oven
temperature increases. The microprocessor reads the
resistance of the oven sensor, and compares it with a
programmed temperature set into the control. When the
resistance of the oven sensor indicates the temperature
in the oven is about 10°F above the programmed
temperature, the microprocessor opens the relay, which
removes power from the bake circuit and closes the
safety valve. When power is removed from the bake
circuit the oven temperature begins to lower. As the
oven temperature lowers, the resistance of the oven
sensor decreases. When the oven drops to about 10°F
below the programmed temperature the resistance of the
sensor tells the microprocessor to close the relay
contacts, and provide power to the bake circuit.
Note: Oven controls may have a spread of more
or less than 20°F. The important thing is
the average temperature in the oven. The
average temperature in the center of the
oven should be within 10°F of the
programmed temperature.
Broil:
When the broil pad is touched, and HI or LO is set with
the up or down arrows, the broil relay on the board
closes, applying line to neutral voltage across the broil
circuit and the oven indicator lights on the control will
illuminate. The broil circuit is a series circuit made up of
the electronic oven control, a silicon carbide igniter that
reduces in resistance as it heats up, and a current
sensitive oven safety valve that needs a minimum of 3.2
amps of current to open. When electrical power is first
applied to the circuit, the resistance of the igniter is high
enough that the current flow in the circuit is below the
amount need to open the safety valve. As electrical
current flows through the igniter it causes the silicon
carbide material to heat, reducing the resistance of the
igniter and increasing the current flow in the circuit.
When the temperature of the igniter reaches around
1800°F the current flow in the circuit exceeds 3.2 amps.
The oven safety valve opens allowing gas to flow into the
broil burner. The gas is then ignited by the heat of the
broil igniter and the oven begins to heat up.
In the tip of the oven sensor is a positive coefficient
thermistor that increases in resistance as the oven
temperature increases. The microprocessor reads the
resistance of the oven sensor and compares it with
programmed temperature set into the control for HI or LO
and will cycle the burner when the temperature is
reached.
Clean:
After the door is closed, the clean pad is touched, a clean
time is set, and the latch handle is moved to the lock
position, contacts COM to NO of the lock switch close
telling the electronic oven control that the door is locked.
“Clean” and “on” appear in the display and the control
closes the bake relay providing power to the bake circuit.
The oven starts to heat. When the temperature in the
oven reaches around 500°F the bimetal tab on the lock
mechanism rotates and prevents the door from being
unlocked. The clean temperature is preset into the
control at around 860°F. It takes about 45 minutes for the
oven to reach 860°F. When the temperature is reached,
the control cycles the bake burner off and on to maintain
the temperature until the clean time is completed. When
the clean time is completed the control removes power
from the bake circuit and the oven cools down. When the
temperature in the oven goes below 500°F the bimetal
tab has turned and the door can be unlocked.