Frymaster H50 Series Service And Parts Manual page 34

The oil return line heater tapes in the Filter Magic system are wired directly into the line VAC
source and remain energized as long as the unit is plugged in. The filter pan suction tube heater
tape, however, is wired into the 24 VAC circuit. The suction tube tape is activated only when the
filter pan is positioned all the way to the rear of the cabinet, allowing a pair of "bullet" contactors
mounted on the pan to touch a corresponding pair of contactors mounted on the cabinet frame.
For FootPrint III systems built before August 1997, all heater tapes are wired directly into the line
VAC source. They remain energized as long as the unit is plugged in. In systems built in August
1997 and later, oil return line heater tapes have been eliminated. In these units, the only heater tape
used is on the suction tube and pump. This tape is still wired directly into the line voltage. A pair of
vacuum-breaking solenoids is wired into the 24 VAC circuit.
In units built from August 1997 onward, the oil return system allows oil to drain back to the filter
pan when the filter system is turned off, eliminating the need for most heated oil return components.
For a short time, one-piece, welded oil return manifolds were used. The one-piece manifolds have
been replaced with Dormont stainless steel flexlines and nipples and are no longer available.
PRE-AUGUST 1997 VS CURRENT DESIGN FP-III FILTRATION SYSTEM
Original System
Return lines and manifolds wrapped with silicone
strip heaters and aluminum tape.
Filter base assembly connected to unit with a
black, heated return hose beneath the filter.
Filter base assembly equipped with swivel cast-
ers.
Operator-removable filter base assembly. (Filter
base assembly stoplocks in cabinet can be ro-
tated to remove tray.)
Oil remains in return lines when filter system is
turned off.
Power Shower Sub-System
A solenoid vent valve is mounted on the left end of the front oil return assembly. It prevents
vacuum-lock of the system as oil drains back to the filter pan when the unit is turned off. The
solenoid valve is connected to the square drain sub-system by a clear ⅜" O.D. Teflon tube and
threaded fittings. Stainless steel Dormont flexlines connect the manifolds to the valves. Standard
½" X ½" X 90º black metal street elbows are used to make the connections.
A 22-inch Dormont stainless steel flexline, running above the filter assembly, connects the front oil
return assembly to the rear manifold.
Filter Base Assembly and Pump Sub-System
Casters have not been used on filter base assemblies built since August 1997. When the casters were
eliminated from the filter base assembly, the assembly was redesigned to prevent it from being taken
out of the cabinet without removing a set of machine screws and nuts.
A new Teflon hose with a braided stainless steel covering connects the pump to the rear manifold
and replaces the heated hose running from the pump discharge under the unit to the Power Shower
Redesigned System
No heater strips or aluminum tape on return
lines.
Non-heated Teflon hose with a swivel joint con-
nects the filter base assembly to the unit above
the filter.
Filter base assembly has no casters.
Filter base assembly is not removable except by
a qualified service technician. (Filter base as-
sembly stoplocks fitted with a screw and nut to
prevent filter removal.)
Oil gravity-drains back to the filter pan when filter
system is turned off, leaving no oil or shortening
in return lines.
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