Solenoid Valve Island Support: Boiler Testing, Stem Cleaning, and Manifold Leak Check

1. General scope and purpose

This technical support manual applies to the solenoid valve island used in industrial air line control systems. Valve island maintenance is performed during periodic maintenance or when malfunctions in the system are detected. The purpose of this manual is to ensure the safe and efficient operation of the valve island, and to identify and correct malfunctions.

2. Safety before starting work

Important: Perform a lockout/tagout (LOTO) procedure before starting service to avoid unexpected movement or energy. Use personal protective equipment (protective gloves, goggles, helmet).

Caution: High voltages or fluids may remain when working with solenoid valves. Perform maintenance only after the system is completely shut down.

3. Necessary tools and materials

Tool / material	Specification	Quantity
Torque screw	0–100 Nm	1
Multimeter	0–500 V, 0–20 MΩ	1
Vacuum cleaner	0.5–2.5 mm	1
A laser for measuring parallelism	±0.02 mm	1
Compressor	0–10 bar	1
Pressure manometer	0–15 bar	1
Cleaning products	For suction and removal of liquids	1

4. Before servicing: inspection instructions

Item	Verification	Acceptance / rejection criterion	Notes
1	Shutting down the system	Power is completely off	Apply LOTO
2	No pressure	Pressure on the manometer ≤ 0.1 bar	Use a vacuum cleaner
3	Lack of fluids	There are no cleaning products	Clean as you work
4	Sanitary floor	The valves are clean	Use a vacuum cleaner

5. Step by step procedure

Boiler Testing
1. Connect the multimeter to the boiler. Set the resistance measurement mode. The resistance of the boiler should be within 100-120 ohms.
2. Measure the voltage on the boiler. The voltage should be within 230 V ± 10%. If a deviation is detected, replace the boiler module.
3. Error: incorrect setting of the multimeter.
Stem Cleaning
1. Unscrew the fitting to remove the stem. Use a vacuum cleaner to remove accumulated liquids.
2. Measure the distance between the ends of the rod. The distance should be 10–12 mm. If wear is found, replace the rod.
3. Error: not removing fluid.
Checking for Manifold Leaks
1. Connect the vacuum cleaner to the manifold. Press the valves to create a pressure of 1-2 bar.
2. Use a manometer to measure pressure. The pressure should remain stable for 5 minutes.
3. Error: Incorrect installation of the sucker .
Assembly and fixation
1. Return the stem to the manifold. Use a torque screw with a range of 0-100 Nm for fixing.
2. Check the distance between the rod ends. The distance should be 10–12 mm.
3. Error: not using the correct torque screw.

6. After service: inspection

Test	Expected result	Actual result	Pass/Fail
Boiler resistance	100–120 Ohms
Boiler voltage	230 V ± 10%
Manifold pressure	1–2 bar
The distance between the ends of the rod	10–12 mm

7. Technical assistance

Symptom	A possible reason	Correction
Unstable pressure	Manifold leak	Check the pressure and repair the leak
Incorrect operation of the valve	Worn stem	Replace the stem
Incorrect resistance measurement	Incorrect installation of the multimeter	Check the multimeter installation

8. Recommended maintenance schedule

Task	Frequency	Estimated duration	Skill level
Boiler testing	monthly	15 minutes	Average
Cleaning the stem	Quarterly	30 minutes	Average
Leakage check	monthly	20 minutes	Average

9. List of spare parts

Part description	Normal specification	UNITEC-D category
Boiler module	230 V, 100–120 Ohm	UNITEC-D 4567
stock	10–12 mm	UNITEC-D 1234
Vacuum cleaner	0.5–2.5 mm	UNITEC-D 8901

For a complete parts list and additional information, go to https://www.unitecd.com/e-catalog/.

10. Reference books

This manual complies with DSTU 3030:2014, EN 12261, ISO 10424 and ISO 8068. Refer to the original manufacturer's documentation for additional information.