Water Pumps & Accumulator Tanks

Problems with Pulsating Water Flow?

Does your water pump continually cycle off and off when you open a tap slightly, or when you are running an evaporative air conditioner? Do you get water hammer when you turn your taps off and on? Do you have problems controlling the temperature of the hot water because of water flow variations?

If so, then you may need to consider adding an accumulator tank to your water supply system.

What is an Accumulator Tank?

An accumulator tank is a pressurised container that attaches to the output line of your pump. It is pressurised to the normal output pressure of the pump and provides a small reservoir that supplies water when a tap is turned on. When the reservoir starts to empty, the pump comes on and refills the reservoir and then stops. This means that the pump runs less often and comes on fully when it does.

This results in a smoother water flow, reduces water hammer and decreases on/off cycling of the pump increasing its lifetime and reducing battery consumption and operating noise. The smoother water flow also gives better control of the temperature of hot water. If you have a houseboat with evaporative air conditioning, you will find an accumulator pump will prevent the water pump cycling so often, allowing it to run much cooler and last longer.

Water Pump Runs Continually Even When All Taps Are Off?

If your water pump continues to operate or cycle long after you have turned off all taps, it is likely that you have air in one or more of your water pipes. Often you can solve this problem by turning on the taps and letting the air out. You will often know when the air comes out as the tap will "spit" and/or the water flow is erratic.

The other thing that can cause the pumps to continue to cycle is that the accumulator is set to the wrong pressure. Most small marine accumulators can be pressurised via a bicycle tire type valve. This pressure needs to be matched to the operating pressure of your pump for it to function correctly. Please consult the accumulator's manual for the correct adjustment procedure and to confirm that it is compatible with the pump to which it is connected.