Installation of solenoid valves
Before starting the installation, it is important to verify that the solenoid valve is suitable and safe for the desired application by carefully reading the user manual and safety instructions associated with the brand and type of valve. Check the valve properties on the type label and verify if the specifications match with the requirements of the application. The image below shows an example of type labels with an explanation of the various parameters.
- Make sure that the circuit is not under pressure and that the system is cooled down before proceeding.
- Check the pipes for dirt (rust particles, cuttings, leaves etc). It is recommendable to flush the pipes before installing the valve. Small particles of dirt in the pipe can enter the valve and lead to blockages or leakage. This is one of the main reasons why solenoid valves malfunction. This problem can be solved by opening and cleaning the valve, but it is better to prevent dirt from entering the valve. If you are not sure that the medium is absolutely clean, you can install a pipe filter on the inlet side of the solenoid valve.
Positioning of the solenoid valve
- It is recommended to install the valve in a dry and ventilated environment. The valve gets hot during use. To allow for cooling, sufficient space must be maintained around the valve.
- Most solenoid valves can be used in one flow direction only. Be aware of the flow direction of the medium when installing the valve. Often the correct flow direction is indicated by an arrow on the valve body. The pipes on both sides of the valve must be securely fastened. Use a wrench for both the valve and the pipe while tightening. Prevent unnecessary stresses in the system.
- The best way to install the valve is with the coil facing upward with a maximum deviation of 90 degrees (see picture). This reduces the risk of collecting dirt in the valve.
Mounting the coil
Mount the coil on the solenoid valve. Never connect the coil to the power supply when it is not mounted on the solenoid valve! The coil may burn out. Follow the user manual to ensure correct assembly of the parts. Tighten the nut sufficiently to make sure that the coil does not rotate or vibrate, but avoid over tightening in order to prevent damage. A guideline for the tightening torque is 5 Nm.
Installation of the connector
Follow this step if the coil is fitted with a DIN-A or DIN-B connector.
- Use a round cable. Connect terminals (1) and (2) to the power supply. The polarity does not matter.
- Always connect the ground. Never use the piping as earthing.
- Connect the connector to the coil. Make sure that no moisture can come between the coil and the connector. Use a torque of 0.5Nm for the mounting screw.
- Position the cable in a way that (condensation) drops can not slide along the cable into the connector.
Only turn on the power supply when the valve is correctly installed and can be started safely. Please note that pressure may be present in the system.
During use the coil gets hot.
In case the solenoid valve does not function properly after installation, in most cases this is easily corrected. These are the most common reasons:
- The valve is blocked because of dirt. Small dirt particles can block the small channels and openings in the valve. Although the pipes seem clean during installation, it still regularly happens that the pipes contain dirt like rust particles, sand, cutting chips etc. If this happens, open the valve carefully and clean the parts. Always follow the instructions in the user manual. Ensure that the valve is properly reassembled.
- The valve is connected in the wrong flow direction. Check the flow direction that is indicated on the valve body with an arrow or text and reverse the valve if necessary.
- The valve is indirectly operated and the differential pressure is too low. If the pressure across the indirect operated valve is too low (less than 0.5 bar), the valve will not properly open. In this case, a (semi-)direct operated valve should be used.
- You experience water hammer. Water hammer is a typical consequence of a high flow rate and pressure in pipes with small diameters. There are several solutions for this problem:
- Increase the pipe diameter to reduce the fluid velocity.
- Reduce the pressure with a pressure reducing valve before the solenoid valve.
- Dampen the water hammer by using a flexible hose or buffer before the solenoid valve.
- Use a solenoid valve with a longer response time. This reduces the pressure transients.