High Temperature Limit Switch; Electronic Key Pad Timer - Cleveland steamcraft 21-CET-8 Service Manual

Page 90 Model 21-CET-8 Service Manual

High Temperature Limit Switch

Electronic Key Pad Timer

1. Set the voltmeter to the 250 VAC scale.
2. Set the ON/OFF switch to the ON position.
3. Before proceeding to step 4, wait until water fills the float cylinder to normal
operating level.
4. Set TIMED/MANUAL switch to MANUAL. Check that the heater contactor
energizes: 120 VAC from the heater contactor black wire connection to the heater
contactor white/black wire connection.
• If the meter reads 120 VAC, the high temperature limit switch is good. End this
procedure here.
• If the meter does not read 120 VAC, continue this procedure with step 5.
5. Check for 120 VAC across the high temperature limit switch terminals.
• If the meter reads 120 VAC, replace the high temperature limit switch.
• If the meter reads 0 VAC, continue this procedure with step 6.
6. Check for 120 VAC from the TIMED/MANUAL switch orange wire connection to the
ON/OFF switch white/black wire connection.
• If the meter does not read 120 VAC between these test points, test the
TIMED/MANUAL switch.
• If the meter reads 120 VAC between these test points, the fault is not in the high
temperature limit switch.
a. Check the black and white/black wires to the high temperature limit switch,
float assembly, and the contactor for continuity, and secure connections.
Replace or repair faulty wiring and connections.
b. Test float low limit switch.
c. Test the contactor for an open coil.
The electronic key pad timer is a sealed unit Replacement of this unit is the remedy
for most timer malfunctions. A few timer malfunctions are caused by other SteamCraft
3.1 components. The symptoms of these malfunctions and the associated testing are
listed below.
1. Remove all food and trays from compartment.
2. Refer to the Final Setup and Checkout section at the end of Chapter 2. Observe the
operation of the SteamCraft 3.1 components during these opera-dons.
a. Perform the Setup and Blowdown Inspection, and steps 1 through 5 of the
Operating Tests - Key Pad Control Panel section. These tests cover
blowdown and manual operations. Malfunctions observed during these
operations are due to component faults outside of the timer and timer
circuits.
b. Perform steps 6 through 10 of the Operating Tests • Key Pad Control Panel
section. These steps cover timed operations. Malfunctions observed during
these operations may be caused by faulty timer or timer
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