Heating Elements Diagnostic Check - Vulcan-Hart C24EA Series Service Manual

C24EA SERIES ELECTRIC CONVECTION STEAMERS - HEATING ELEMENTS AND CONTACTORS
Fig. 31
6. Reassemble parts removed in reverse order.
7. Check steamer for proper operation.
HEATING ELEMENTS DIAGNOSTIC
CHECK
Certain procedures in this section
require electrical test or
measurements while power is
applied to the machine. Exercise
extreme caution at all times and
follow Arc Flash procedures. If test
points are not easily accessible,
disconnect power and follow
Lockout/Tagout procedures, attach
test equipment and reapply power to
test.
1. Check voltage across heating element lead wires
at the limiting and regulating contactor terminals
and verify against data plate.
A. A. If voltage is correct, check current draw
(step 2).
B. If voltage is not correct, check the following:
1) Voltage supply to steamer.
2) Fuses or breaker blown.
3) Power to contactor coils.
4) Contactors not pulling in (mechanical
problem).
2. Check current draw (amps) through heating
element lead wires using an amp clamp meter.
F35453 Rev. A (0119)
NOTE: Checking current draw is the preferred
method over a resistance check when an amp clamp
meter is available.
A. If current is correct, then heating element is
ok. See table for proper values.
B. If current is not correct, turn power switch off
and disconnect power to machine.
1)
3. If unable to check current draw, a resistance
check may indicate a malfunctioning element.
A. Turn power switch off and disconnect power
to machine.
B. Disconnect heating element lead wires and
check the individual element resistance
using a VOM.
C. If resistance readings are not correct,
replace heating element.
4. Check steamer for proper operation.
KW, CURRENT AND RESISTANCE PER
VOLTAGE
a
208
a
240
b
480
a
208
a
240
b
480
a
Dual voltage elements.
b
480V elements are connected in Wye
configuration for 277V across each element.
NOTE: Values in table are nominal. Tolerance is ±10
%.
Page 20 of 75
Install a replacement heating element.
ELEMENT
RESISTANCE
KW CURRENT
8.0 12.8
10.5 14.8
8.0 9.6
8.0 12.8
10.5 14.8
8.0 9.6
(OHMS)
16.2
16.2
28.8
16.2
16.2
28.8