Models 24-CGA-10, and 24-CEA-10
SteamCraft 10 Service Manual, Chapter 6
Page 93
Solenoid valves in the SteamCraft 10 control the flow of water, steam, and
drainage. In addition, the Model 24-CGA-10 units have automatic gas valves with
solenoid actuators. The Component Test Procedures detail testing each of these
solenoid valves. This section provides general and reference information about
these valves.
General Considerations
When testing or replacing a solenoid valve, check the valve for correct flow
direction. Markings on the valve body indicate IN for the inlet, OUT for the outlet,
or both. Some valves use an arrow to indicate the proper flow direction. Valves
installed backwards do not work correctly.
Before testing valve operation, verify that water, steam, drainage, etc. supply is
available to check flow through the valve. For example: When testing a water
control solenoid valve, first check that external supply valves are open.
When power is first applied to a properly operating solenoid, an audible click can
be heard. While energized, the solenoid hums at low volume. The click sound
usually indicates a properly operating solenoid.
Energized solenoids generate a magnetic field that can be detected with a steel
screw driver. Note that some stainless steels, brass, and aluminum alloys are not
magnetic and will not be effected by the magnetic field.
Low voltage (below 90 VAC) will cause a solenoid to hum loudly or chatter.
• Check for loose connections to the solenoid.
• Check power supply to the solenoid for the proper voltage for the model being
tested. Refer to the schematic diagram in Chapter 7.
Normally Open and Normally Closed Valves and Contacts
Whether troubleshootin g a system or a component, it is important to know if the
solenoid valve is normally open or normally closed.
• A normally open valve or contact is open until the solenoid is energized. It
closes when the solenoid is energized, and remains closed while the solenoid
remains energized. It opens when the solenoid is de-energized.
• A normally closed valve is closed until the solenoid is energized. It opens when
the solenoid is energized, and remains open while the solenoid remains
energized. It closes when the solenoid is de-energized.
Refer to Figure 6-1 for the normal state of each valve in the SteamCraft 10.
Water Pressure and Control Valves
The SteamCraft 10 water control solenoid valves operate at a maximu m pressure
of 60 psi. Higher pressure causes unnecessary valve wear and requires frequent
valve replacement. If necessary, install a pressure regulator set at 50 psi.
Measuring Resistance Through the Solenoid
To determine if a valve solenoid is operable, measure the resistance through the
solenoid coil. If the reading is zero, the coil is shorted. and the solenoid valve
should be replaced.
Jammed or Blocked Valves
If the electrical connections and solenoid actuator are good but the valve does not
operate correctly, the valve may be jammed in position or blocked at the inlet or
outlet.
Cleveland Range, Inc.
Printed 3/93
Solenoid Valves
