The "Power Source" of Non-Pressurized Solar Water Heaters: The Water Supply Tank

In today's pursuit of green and energy-efficient living, solar water heaters have become a standard feature in many households. However, when searching for "non-pressurized solar water heater," we often encounter keywords such as "pressurized," "water tower," and "booster pump." Do you truly understand the crucial role that seemingly ordinary water tank plays in a non-pressurized system? It's not just a water storage device; it's the "heart" of the entire system's smooth operation.

I. Core Concept: What is a Non-Pressurized Solar Water Heater?

Simply put, a non-pressurized solar water heater's heat storage tank is open to the atmosphere and is not subject to water pressure from the mains. Its operation relies on a separate, higher-level water supply tank (often called a "makeup tank" or "storage tank").

Working Principle:

Tap water is first pumped into the higher-level supply tank. Thanks to gravity (water flows downward), cold water from the supply tank naturally flows into the vacuum tubes or flat-plate collectors of the solar water heater.

After the cold water is heated by the sun, the hot water rises due to its reduced density and returns to the top of the insulated water tank of the water heater, completing the cycle.

When we turn on our hot water taps at home, hot water also flows out by gravity, while the supply tank continuously replenishes it with cold water.

2. Supply Tank: The "Power Source" of the Non-Pressure System

The supply tank is the source of water pressure for the entire system. Its importance lies in:

Providing Stable Water Pressure: The installation height of the tank determines the pressure of the hot water output. The higher the floor, the higher the tank is placed, the greater the gravitational potential energy, and the stronger the hot water output. This is one reason why many users search for "What to do if my solar water heater has low water pressure"—the supply tank may not be high enough.

Ensures a continuous water supply: It acts as a buffer storage device, ensuring sufficient water for heating and supplying the solar water heater even during unstable tap water pressure or temporary water outages.

Protecting system safety: Because it is open to the atmosphere, it prevents excessive pressure from water expansion or steam accumulation, fundamentally eliminating the risk of a tank burst and providing exceptional safety.

3. Commonly used accessories for compact, non-pressurized solar water heaters

1) Water supply tank

2) Booster pump: The magic weapon to solve insufficient water pressure

When the water supply tank is installed at an insufficient height, resulting in insufficient water pressure at the top floor or when multiple water points are used simultaneously, installing a "hot water booster pump" is an immediate solution. It can be connected in series to the hot water pipe to specifically boost the pressure of the hot water outlet.

3) Pipe selection and insulation

The pipes connecting the water supply tank, water heater, and water points are crucial. Use high-temperature-resistant PPR or metal pipes. At the same time, effectively insulating outdoor pipes, wrapping them with insulation and UV-resistant tape, is crucial for preventing heat loss and freezing during winter.

4) Automatic Control and Water Level Display - Solar Controller

To prevent overflowing or drying up of the water supply tank, you can install an automatic water level controller. This automatically fills the water tank and displays the water level and temperature in real time.

In short, by understanding the role of the water supply tank and properly arranging the appropriate accessories, you can fully utilize the economical, safe, and durable advantages of non-pressurized solar water heaters and enjoy a constant supply of comfortable hot water.