Is a variable frequency system water pump better than a pressure tank operation?

VFD can control the water pump motor and the water speed base on the water usage. With the ability to control the speed of the pump, the water pressure can be increased and decreased in the same flow system and the same pump circle.

In the traditional method of operation, pumps worked in conjunction with a proper size pressure tank and a pressure switch. The pressure tank held a significant volume of captive air and when the pump is turned on, water is forced water into the air-filled pressure tank to support the water usage until the water pressure reduces to the set level.

Let’s discuss the way of water usage.

Most of the water usage such as restaurants, public toilets, or home showers does not take a long time continuous water usage. Most of the time is an On-Stop and On-Stop process.

In the VFD system, the pump stops as soon as the water flow stops, such as turning a water faucet.

As the most common mechanical concept, high energy is used at the pump starting period, not the running time.

A proper pressure tank can allow the water pump to run at full speed to fill up the water tank, and the pressure tank supplies a good amount of water to supply several times of water usage circle.

The system with pressure tanks can have 80% less pump circle than the VFD system in the family home water system for the ratio. On the other hand, the expensive cost of VFD is also the downside of the VFD system.

The water system with pressure tanks has the best energy efficiency compared to the VDF system.