How to solve electrical heater noise

Auxiliary electric heater after a long time, will produce some noise not too coordinated, how to solve electrical noise heater?

First of all, we need to adjust the pressure can be adjusted by auxiliary electric heater inside the pressure gauge shows pressure;

And soda mixed water outlet installation of heat pumps for pumping water, which will then form a negative pressure zone, reducing vibration and reduces noise.

When the auxiliary electric heater when excessive vibration or noise is too much, you can try using one of the above methods to solve the problem.