Electrolux FMB330RGB0, Service Manual

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The next filter passes through the
center of the stainless steel filter
and has larger opening. This filter
extends all the way to the bottom
of the sump and seats into the
center of the sump where the water
exits into the drain pump. As food
and other items are removed from
the load they fall into the bottom
of the tub, where two holes on the
underside of the lower spray arm
spray water on the tub bottom
moving them to the filter. Larger
items will fall through the larger
openings in this filter and down into
the sump. As the drain cycle begins
this section of the sump is cleared
first.
The third filter is a large wire mesh filter, this filter is around
the outside of the center filter. It allows water to enter the
outer section of the sump for the wash pump but not allow
trapped food to leave the center section. This third filter is
the only filter that could be installed wrong , there so it is
marked showing which is the “TOP”.
The customer is instructed to remove these filters
periodically for cleaning. When removed the center
section from the sump any food debris found in the
bottom of the sump needs to be removed. This will help
keep from stopping up the drain pump as well as reduce
redeposit on future cycles.
Thermostats
Control Thermostat
The control thermostat is a normally open thermostat used
when the option for a Hi – Temp wash is selected. The
timer advances automatically through the wash cycle to a
point at which the timer motor contact opens, stalling the
timer. If the Hi – Temp option was selected the timer will
not advance beyond this point until the water temperature
in the tub raises to close the control thermostat. After
the thermostat closes, the timer advances on to the
next cycle. The time needed for this to occur can vary
depending on incoming water temperature and load.
Safety Thermostat
The safety thermostat is a normally closed thermostat
wired in series with the heater that will open if the
temperature in the tub raises over 190°. This thermostat
only disconnects power to the heater so the dishwasher
will continue the cycle.
Mesh Filter
Control and Safety Thermostats in the Mount assembly
Mounting onto the sump
Control thermostat
Safety thermostat
Both the control thermostat and the safety thermostat
are mounted in one mount assembly and this assembly is
locked to the side of the sump. In the mount, there are two
small springs per thermostat pushing up to put pressure
on the thermostat for better contact with the tub. Both
thermostats will come as an assembly and need to be
replaced as an assembly. When replacing the thermostats
be sure to use Thermal Mastic on the new parts before
installing them to the sump.
Heater
The purpose of the heater is to maintain and increase
water temperature during the wash and rinse cycles and
to assist in drying the dishes. The heater is a 525 watt
element mounted in the right rear of the tub using a single
mounting flange with a gasket molded to the under side.
The tub has two heater supports welded to the bottom to
support the heater on the left side.
Tub and Door Attachments
Air Gap
The air gap is needed for filling the dishwasher with clean
water. There is a second purpose for the air gap, this is to
allow outside air to enter the tub in the dry cycle. As steam
rises in the tub and exits out the vent, cooler air enters
through the air gap to create air movement in the tub
which speeds drying. The air gap is mounted to the right
outside of the tub.