The noise problem of residential solar energy has been solved

Investigation of noise sources

Operating noise of the water pump

The water pump in the residential solar system is one of the common noise sources. When the water pump is in operation, the impeller inside rotates at high speed, generating friction and impact with the water. At the same time, the motor also vibrates, all of which can lead to noise. For instance, when the bearings of a water pump wear out, the impeller will rotate unsmoothly, thus generating considerable noise. You can approach the water pump and listen carefully to the sounds it makes during operation to determine if there are any abnormal humming or creaking sounds.

In addition, the installation position and fixation method of the water pump will also affect the noise level. If the water pump is not installed firmly, it will generate greater vibration and noise during operation.

Fan noise (for some devices with heat dissipation function)

In some solar energy systems, devices such as inverters or controllers are equipped with fans for heat dissipation. During the rotation of the fan, both the friction between the blades and the air and the operation of the motor will generate noise. For instance, when dust or foreign objects adhere to the blades of a fan, it will disrupt the balance of the blades, causing the fan to generate considerable noise during operation. It can be judged by observing whether there are foreign objects on the fan blades and sensing the flow of air and noise around the fan during operation.

Pipeline water flow noise

When water flows in the pipes of a solar water heating system, if the water flow speed is too fast, there is air in the pipes, or the pipes are installed improperly, noise may be generated. For instance, when water flows through elbows, valves and other parts, if the water flow speed is relatively high, turbulence will occur, thereby generating noise. You can follow the direction of the pipe and carefully listen to the sound of water flow inside the pipe to determine if there are any abnormal sounds such as flowing water or air passing through water.

Equipment resonance noise

When various devices in a solar energy system are in operation, they will generate vibrations. If the connections between the devices and the installation brackets, walls, etc. are not firm or there are gaps, resonance may occur, thereby generating significant noise. For instance, when the vibration frequency of the inverter is close to the natural frequency of the installation bracket, resonance will occur, significantly increasing the noise. You can determine whether there is a resonance problem by gently shaking the device and observing if there are obvious changes in shaking and noise.

Targeted solutions

Pump noise treatment

Replace the worn parts

If the bearings of the water pump are found to be worn, new bearings should be replaced in time. At the same time, check whether the impeller is damaged or deformed. Replace it if necessary. The new bearings and impellers can ensure the smooth operation of the water pump and reduce the noise caused by friction and vibration.

Adjust the installation position and fixation method

Make sure the water pump is installed on a solid foundation and fixed with appropriate shock-absorbing pads or shock absorbers. Shock-absorbing pads or shock absorbers can effectively absorb the vibrations generated during the operation of water pumps and reduce noise transmission. For instance, rubber shock-absorbing pads can be used. Placing them between the water pump and the installation foundation can significantly reduce vibration and noise.

Control the operating time of the water pump

According to the actual water demand, the operating time and start-stop conditions of the water pump should be reasonably set. Avoid the continuous operation of the water pump for a long time to reduce the time noise is generated. The operation time of the water pump can be precisely controlled by installing a timer or an intelligent control system.

Fan noise treatment

Clean the fan blades

Regularly clean the fan blades to remove dust and foreign objects on them. You can use a soft-bristled brush or a hair dryer to gently clean the surface of the blades to ensure they remain balanced and clean, and reduce the noise caused by blade imbalance.

Replace the aging fan

If the fan has been in use for a long time, the motor ages or the blades are severely worn, it should be considered to replace it with a new fan. New fans usually have better noise reduction performance in design and manufacturing, which can effectively reduce operating noise.

Adjust the rotational speed of the fan

Under the premise of ensuring the heat dissipation effect of the equipment, adjust the rotational speed of the fan appropriately. Reducing the rotational speed of the fan can decrease air friction and vibration, thereby reducing noise. The rotational speed of the fan can be adjusted by regulating the control circuit of the fan or using a frequency converter.

Pipe water flow noise treatment

Install the pressure reducing valve

If the water flow speed is too fast and causes noise, a pressure reducing valve can be installed on the pipeline to lower the water pressure inside the pipeline, thereby reducing the water flow speed. The pressure reducing valve can adjust the water pressure according to actual needs, keeping the water flow speed within a reasonable range and reducing water flow noise.

Expel the air in the pipeline

Regularly perform exhaust operations on the solar water heating system to remove the air inside the pipes. An exhaust valve can be installed at the high point of the pipeline. When the system is in operation, the air will be automatically discharged from the exhaust valve. Make sure the pipeline is filled with water to avoid the sound of air passing through water due to the presence of air.

Optimize pipeline installation

Check whether the installation of the pipeline is reasonable to avoid sharp bends, dead bends and other situations in the pipeline. For parts such as elbows and valves, flexible joints or noise-reducing elbows can be used for connection to reduce the noise caused by the impact of water flow. At the same time, ensure that the pipe supports are installed firmly to avoid noise caused by pipe vibration.

Equipment resonance noise treatment

Strengthen the fixation of equipment

Check whether the connection between the equipment and the installation bracket and the wall is firm. If any is loose, it should be tightened in time. Fasteners such as bolts and nuts can be used to firmly fix the equipment on the installation foundation to reduce equipment vibration.

Increase damping materials

Add damping materials such as rubber pads or foam plastics between the equipment and the installation base or around the equipment. Damping materials can absorb the energy generated by the vibration of equipment, reduce the occurrence of resonance phenomena, and thereby lower noise.

Adjust the position of the equipment

If the resonance of the equipment is caused by its natural frequency being close to that of other equipment or building structures, you can try adjusting the position of the equipment to change its vibration frequency and prevent resonance from occurring.

Daily maintenance and prevention

Regular inspection and maintenance

Formulate a regular inspection and maintenance plan to inspect and maintain each device in the solar energy system. Timely detect and handle problems existing in the equipment, such as wear, loosening, aging, etc., to prevent the problems from worsening further and causing increased noise. For instance, conduct a visual inspection and operation test of equipment such as water pumps and fans once a month, and carry out a comprehensive inspection and exhaust operation of pipelines once every six months.

Keep the equipment clean

Regularly clean the equipment in the solar energy system, such as collectors, water tanks, pipes, etc. Keeping the surface of the equipment clean and reducing the accumulation of dust and debris can not only improve the operational efficiency of the equipment but also lower the noise caused by dirty equipment.

Use the system reasonably

Use the solar energy system correctly in accordance with the user manual to avoid overuse or improper operation. For instance, do not frequently start and stop the water pump and fan to avoid unnecessary impact and damage to the equipment, thereby reducing noise generation.