Market Forge Industries ST-E STEAM IT, Service Manual

Page: 5 / 25

SEPTEMBER 14, 2017 5 ST-E ELECTRIC PRESSURE COOKER
ADJUSTMENTS & PARTS REPLACEMENT
Dial Adjustment
Two dial settings determine the operational range of the
element control switch. The larger dial (D) determines the
maximum build-up of cylinder steam pressure while the
smaller dial (E) governs the range of differential between
the switches cut-in and cut-off points. Should a lower cyl-
inder cooking pressure be desired, adjust the large dial
(D) by inserting a screwdriver onto the slot (B) found at
the center and turning it slightly counterclockwise to lower
the pressure. Clockwise rotation will increase the pres-
sure.
Pressure must not be adjusted to exceed 14 lbs. as the
safety valve is set to automatically open just above this
point. The cut-in and cut-off points of the element control
switch may be adjusted by rotating the small screw at the
center of the smaller dial (E). Normal factory setting is
for a one pound differential between cut-in and cut-off. To
increase the range of differential, rotate the screw coun-
terclockwise.
Check adjustments through a trial cycle by observing
pressure gauge reading when it clicks in after cylinder
cooking. The differential in pressure as read on the pres-
sure gauge should at these points be approximately one
pound.
Recalibrating
The element control switch may be recalibrated should
it vary somewhat through usage from its original factory
setting.
At the precise moment of contactor “clicked-out”, the dial
setting of the element control switch and the steam pres-
sure gauge reading should both be 14 lbs. A slight over-
ride of steam pressure build-up will normally occur and in-
dicate itself on the pressure gauge after the contactor has
“clicked-out”. This is normal and it not to be interpreted as
an element control switch out of calibration.
PRESSURE CONTROL SWITCH
(Formally knows as the element control switch)
NOTE: Models built after September 1980 use 2 Barks-
dale Pressure Switches in place of the White-
Rodgers Element Control Switch and Timer Con-
trol Switch.
Operating Pressure Adjustment
The operating pressure is determined by setting the right
switch (A) at approximately 10 PSI and the left switch (B)
at approximately 14 PSI. Both switches were set At the
factory. These settings can be verified by looking through
the slot ( in the red rectangle ) and observing the alignment
of the black line inside with the white scales on either side
of the slot. To readjust, turn the white knurled knob in ap-
propriate direction to raise or lower pressure.
WARNING
Because power must be on to adjust pressure
switches, be sure to protect against electri-
cal shock. Check adjustments through a
trial cycle and observe pressure readings on
pressure gauge when switch (B) clicks off at
maximum cylinder pressure and when switch
(A) clicks on after cylinder cooking. Making
adjustments are needed, being careful not to
let switch (B) pressure be set to exceed 14 lbs.
Since the safety valve is set to automatically
open just above this point.
Recalibrating Pressure Control Switch
The actuation valve ( differential ) is factory set and cannot
be recalibrated.
CLEANING EXHAUST SILENCER
The exhaust silencer should be removed and cleaned pe-
riodically. As the cooking chamber is exhausted of steam
through the silencer, impurities can build up from food
particles. Cleaning should be frequent enough to prevent
clogging to occur. For this reason, the exhaust silencer is
made easily accessible and simple to remove. To clean:
1. Remove the one piece exhaust silencer from the unit
by unscrewing it in a counterclockwise direction.
2. Clean the silencer by sloshing it in hot soapy water
and rinse it in clear water. If dirt has clogged the si-
lencer, presoak it in alkaline cleaning solution.
3. After cleaning, stand the silencer on edge to allow it
to drain.
4. Screw it back into the elbow of the exhaust valve
clockwise.