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steam
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C U S E R I E S Installation, Operating & Maintenance Manual
31
CHECK
PC Board - Models CU 360, CU 500,
CU 750, CU 1000, CU 1400
1. Prior to checking boiler disconnect boiler electric power sup-
plies at main safety switch or fuse panel. Turn the boiler
switch OFF.
2. Turn the control voltage ON and turn the boiler switch ON.
Measure the voltage across "L1" and "L2" on the 103538C
board. The voltage should be approximately 110 VAC.
3. On the 103538C board, disconnect the wire from the "LO"
terminal and check the voltage across "L2" and "PUMP".
The voltage should be approximately 110 volts (same as
"L1" and "L2"). Connect a jumper between the "LO" and
"GND" terminals. The voltage between "L2" and "PUMP"
should be zero.
4. On the 103538C board, disconnect the wire from the "LO"
terminal. There should be no voltage between the "L2"
and "CONT” terminals. Connect the jumper between the
"LO" and "GND" terminals. The voltage between "L2"
and "CONT" should be 110V.
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Low Water Cutout, Water Feed and
High Water Cutout Probes
Models CU-360 through CU-1400 are equipped with two probes
for low water cut-off (LWCO) and water feed control. Failure to
clean the probes may result in generator not operating, overflow
or element failure.
Turn off all power supplies to
steam bath generator and release pressure to
zero (0 psig) before removing probes.
1.
Probes are located in the top of the generator. Remove cov-
ers and disconnect wires from probes. Note wire connections.
2.
Remove probes using a standard spark plug wrench.
Care should be taken not to damage the insulation.
3.
Check probes for deposits. Use emery cloth to clean probes.
4.
Remove and flush probe isolator (thoroughly) with water. If
clogged, use a long piece of wire to remove obstruction.
Replace if necessary, center probe rod in isolator tube.
5.
Use teflon tape on probe threads and reinstall.
6.
After installation, make sure probe is not touching ground.
With generator drained and probe wires
disconnected, there should be no resistance (X) between
probe and ground. Check for leaks.
7.
To test AUX LWCO, press and hold the manual reset button
on the side of the steam bath generator for 5 seconds.
Steam Solenoid Valve
1.
Check voltage rating of solenoid valve (120 VAC for United
States, Canada, Mexico; may be 220-240 VAC for other
countries).
2.
Check voltage across solenoid coil.
a. If there is voltage across coil and valve does not allow
passage of steam, check for clogged valve. Clean outline
with bottle brush. If solenoid valve is still malfunctioning,
the valve is defective and should be replaced.
b. If there is no voltage across coil, check room temperature
control.
c. There wull be a red dot under “OUT2” on the
Digital 1 Control when there is a call for heat.
d. Ensure, if equipped, the room Timer is On.
_______________________________________________
Digital 1
®
Control and Sensor:
Consult Factory
_______________________________________________
Heating Element
IMPORTANT:
Turn off all power at circuit breaker.
Consult factory for resistance values.
1.
Check power voltage across heating element terminals. Refer
to nameplate data for voltage rating.
Voltage should be as marked on nameplate.
2.
Using an ammeter, measure total current draw as per name-
plate rating. (See also Amperage Chart, page 9.
Each leg should register about the same current reading.
3.
If there is more than one heating element, check amperes of
each element. Each leg of the same element
should register about the same reading for that element.
Reading may be different from other elements
due to KW (Kilowatt) rating of individual heating element.
4.
Check heating element for resistance values. Consult factory
for the resistance values for the element specifications.
Prior to checking boiler disconnect boiler
from electric power supply at main safety switch or
fuse panel. Turn boiler switch to OFF.
CAUTION
!
CAUTION
!
CAUTION
!
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