Accumulator Tanks
What Are Accumulator Tanks?
Accumulator tanks act as a buffer or storage vessel for pressurized water systems. They consist of a flexible bladder contained within a hard chamber that is charged with air. When the pump initially turns on, it fills the bladder with water which compresses the air inside the chamber. As water is drawn from the system, the pressure in the chamber forces the water out, maintaining a steady flow and reducing the frequency of pump cycling. These essential components are installed on the discharge side of pressure water pumps in marine, RV, and motorhome applications to dramatically improve water system performance.
Why Accumulator Tanks Matter for Your Water System
If you own a boat with a pressurized freshwater system that suffers from frequent, noisy pump on/off cycling, adding an accumulator tank can correct this problem, which is often caused by the demand for water exceeding the capacity of the pump or the system's ability to maintain constant pressure. When multiple water outlets are opened simultaneously or when a single outlet is partially closed, it can lead to fluctuations in water pressure and trigger the pump to turn on and off rapidly. By reducing the frequency of pump cycling, the accumulator tank minimizes the noise and wear and tear on the pump.
The accumulator tank provides a reservoir of water that can be accessed when there is a sudden demand for water, such as multiple outlets being used simultaneously. The tank stores pressurized water, ensuring a steady supply even when the pump is not running. This means water delivery is much smoother and the pump doesn't have to run every time you crack open a faucet. For boat owners, this translates to quieter operation during nighttime use, more consistent shower temperatures, and significantly extended pump life.
Key Benefits and Considerations
Accumulator tanks improve onboard water systems by minimizing pump cycling, maintaining consistent water pressure, and extending pump life. When properly sized and installed, these tanks provide immediate benefits: the pump doesn't activate for small water draws like a midnight flush or filling a glass, battery consumption decreases due to less frequent pump operation, and the overall system runs more quietly and efficiently.
Proper sizing of the accumulator tank is essential to ensure it has adequate capacity to meet the demands of the water system. Tank capacity typically ranges from under one liter for compact RV applications to 20 gallons or more for larger vessels with household-level water demands. Tank construction includes models made of plastic, painted steel and stainless steel. Capacities and rated pressure vary widely, so be sure to select a tank that is a match for the system on your boat. Pre-charge pressure should generally be set 2-3 PSI below your pump's cut-in pressure for optimal performance.
Top Brands for Marine Accumulator Tanks
The marine industry relies on specialized manufacturers who understand the demanding conditions of onboard water systems. Jabsco leads the market with their time-tested designs featuring non-corrosive plastic construction with pressurized bladders that reduce pulsation and rapid on/off pump cycling. Bladders are pre-pressurized and their pressure can be adjusted with a standard bicycle pump. Their accumulator tanks range from compact one-liter units to two-gallon models suitable for larger installations.
Groco manufactures the PST series of pressure storage tanks known for pneumatic pressure charges matched to pump cut-on pressure that prevent water logging by separating the air charge from system water pressure with a rubber bladder. The result is smooth pressure delivery, even temperature mix in showers, and reduced pump cycling. Groco tanks are available in capacities ranging from 0.5 to over 6 gallons of drawdown.
Shurflo offers reliable accumulator solutions designed to integrate seamlessly with their popular pump systems, providing the same quality and durability that has made their water pressure products a mainstay in the marine and RV markets. Their tanks help optimize system performance while reducing noise and extending component life.