How to Specify the Right Accumulator Tank

AccuBoost Accumulator tanks offer a great solution to low water pressure in a home, however, with so many different tanks available, choosing the right accumulator for the job can seem like a complicated process.

To help simplify the specification process, our Training Manager, Mike Oxley, explains how to choose the right accumulator tank system.

1. Does the home have a combi boiler or an unvented system?

Accumulator tanks are suitable for both combi boilers and unvented systems. However, while all options are suitable for a combi boiler, a home with an unvented system requires a minimum of 330 or 450 litres capacity.

2. Pumped or unpumped?

A pumped tank should be specified for homes with water pressure below 2.0 bar, water flow below 12L/min, or when the highest outlet is on the second floor or higher. However, if the home has a lead or restrictive mains an unpumped accumulator could still be effective.

All AccuBoost accumulator tanks are available as both pumped and unpumped models.

3. What size accumulator tank do you need?

To specify what size accumulator tank a home needs, calculate the flow rate (l/min) of the outlets in the home that you want to run at any one time. You can then identify the correct accumulator tank sizing to provide this flow rate for a minimum of nine minutes – the average length of a shower.

As a rough guide, here is a breakdown of what pumped tanks can offer for nine minutes (after this they will then continue to offer at least 12l/min through the pump):

60L tank – up to 14l/min

120L tank – up to 16l/min

180L tank – up to 18l/min

330L tank – up to 30l/min

450L tank – up to 36l/min

Our product selector features an accumulator tank calculator which will determine, depending on the flow needed by the outlets in the system, what size accumulator tank is needed.

4. How much space is available?

In general, a 60L model will fit into a standard 500mm kitchen base unit; a 120L model into a 500mm larder style kitchen unit; and the 180L/330L model into a 600mm larder style kitchen unit with the back removed (although the tanks don’t have to be situated in the kitchen).

If space is limited, you may need to specify a smaller tank, which would mean running fewer outlets simultaneously. However, an alternative option would be to link multiple tanks together to gain additional capacity and make the solution flexible to the available space.

5. Still unsure?

If you’re still unsure which accumulator tank is right for your needs, Salamander Pumps has an easy-to-use online product selector tool to identify which tank is best suited to the job in hand.