Solar water heater with solar powered level control operates on its own, from refilling the storage water tank, circulation, and heating the water. The system has a PV panel mounted on top of the water tank, which absorbs sun’s heat to generate electricity that is used to power the Control Valve. The valve is connected to sensors found within the water tank. The sensors sends signals to the control valve whenever the water level goes down, and the valve allows cold water to flow into the tank.

solar powered water heater

What Is PV Panel

PV panel is made up of a semiconductor material that absorbs sunlight, and uses it to generate electricity through a process known as “photoelectric effect”. The system consists of multiple solar PV cells connected together to produce electricity. However, the electricity can only be generated if sunlight of a particular wavelength is absorbed.

The effectiveness of the system increases during sunny weathers, and reduces during cloudy weathers. However, the efficiency also depends on the material used to make the solar cell(s). A solar PV module is used to provide power for Control Valve (in a water heating system) to monitor the level of water in the tank.

How The Solar Water Heater With Solar Powered Control Valve Work (shown in fig 1 and fig 2)

Fig 1
Fig 2

  • The key components in this system include; float level control, upper control, level sensor float, PV panel, Fill System, storage water tank.
  • Float level control maintains the level of water in the tank through the upper control. When water level falls, contact at the float level control will close, making the circuit complete.
  • A signal is sent to the upper control (control PCB) that in turn activates (opens) solenoid valve to fill the tank.
  • During rapid water loss such as pipe or tube breakage, level sensor float falls to the bottom to prevent fill system from allowing water into the tank until the problem is rectified.

How To Find Out Fault Within The System

In most cases, the faulty system is indicated by continuous or constant overflow of water in the storage tank. The following are the steps when you notice such a problem:

  • Lift the nylon tube from the tank port and check if water is constantly flowing.
  • Cover the PV panel from sunlight and see the water flow through the nylon tube. If flow is still constant, check if the solenoid valve is working properly.
  • However, if flow stops after covering the PV panel, it indicates that the float level switch is faulty. You can disconnect the circuit by removing one wire from the control PCB to stop water from flowing through the nylon tube.

The system comes with a manual to assist in the installation process. Once installation is complete, the storage water tank is initially filled using a hose pipe. When the tank is full, the Level Control System takes over the tank level. The Control Valve with the help of sensors is responsible for ensuring automatic refilling of the tank.