Jump to content

What size pressure accumulator for water pump

Recommended Posts

Have a 13 ppm pump on the fresh water system, with a 2 litre (Wave?) accumulator.


The pump label says Flow = 13 lpm, Shut In = 25psi, Shut Off = 41 psi

The accumulator label says Volume = 2 litres, Max Working Press = 10 bar (145 psi)


I'd like to reduce the frequency of the pump having to run when running the tap.


Would fitting a larger accumulator reduce the frequency of the pump running?


I'm thinking the pump stops when the accumulator reaches 41psi, and activates again when it drains to 25psi, so a larger accumulator won't achieve a higher pressure, but may be able to hold pressure above 25 for longer. Is that correct?


Is there a recommended match for pump and accumulator?

Link to post
Share on other sites

The pressure tank is maybe a wee "pressure wave" brand - american made. Creamy white in colour?


The bladder should have approx 27psi in it to operate correctly - about 2psi above the cut in pressure of the pump.


Check that. If it does not give a satisfactory result, you could consider a larger accumulator or putting a check valve in with a 4 or 5mm hole drilled in it. Set it up so the flow out of the accumulator is unimpeded, and the flow in has to pass through the small hole you have drilled. This will reduce the cycling of the pump as it forces the water to the tap much more than the accumulator. Its a very common practice when using pressure tanks on large volume pumps.

Link to post
Share on other sites

Accumulators water capacity is normally roughly half of their total capacity - but the low, cut in pressure, will be before the accumulator is completely empty. I would not have thought you'd get much, water from the tap unless your accumulator is really substantial. Of course, the pump must eventually pump 1 ltr of water for you to get 1ltr out of the tap! So, even though it may start less often, it still really does the same work. The only saving I could see is the slightly more current the pump draws at startup?


I don't have an accumulator though, so I may be wrong - I use a multi diaphragm pump - no accumulator required. IMO simple is good!

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...