Water pump running

[Strettonman]

I’ve just started revamping my water system and have a question regarding how long it should take for the pump to kick in and cut off. 

Before I started hacking it about the pump would kick in within a couple of seconds of opening the cold water bathroom tap and cut off 2 or 3 seconds after closing the tap. The tap was about 20ft from the pump and the accumulator was just next to the pump (mounted horizontally if that is relevant). 

Ive been rejigging the pipework with the accumulator now about 10ft from the pump and mounted vertically. It now takes 10-15 seconds before the pump starts ans it runs on for about 30 seconds after closing the tap. Is this just the accumulator doing the job it’s designed for or is it suggesting something has gone wrong with it ? 

Ive not been on loads of boats but I can’t remember any araying on for 30+ seconds. 

Btw, water flow is good and consistent whether the pump is running or not. 

pump is  2.9bar and rated at 11 ltr/m. Accumulator is probably about 5 ltrs. 

[Flyboy]

51 minutes ago, Strettonman said:

I’ve just started revamping my water system and have a question regarding how long it should take for the pump to kick in and cut off. 

Before I started hacking it about the pump would kick in within a couple of seconds of opening the cold water bathroom tap and cut off 2 or 3 seconds after closing the tap. The tap was about 20ft from the pump and the accumulator was just next to the pump (mounted horizontally if that is relevant). 

Ive been rejigging the pipework with the accumulator now about 10ft from the pump and mounted vertically. It now takes 10-15 seconds before the pump starts ans it runs on for about 30 seconds after closing the tap. Is this just the accumulator doing the job it’s designed for or is it suggesting something has gone wrong with it ? 

Ive not been on loads of boats but I can’t remember any araying on for 30+ seconds. 

Btw, water flow is good and consistent whether the pump is running or not. 

pump is  2.9bar and rated at 11 ltr/m. Accumulator is probably about 5 ltrs. 

It sounds like your accumulator may be over pressurised. What pressure have you pumped it up to ?  I would set it to about 0.2bar (3psi) below the pump cut in pressure.

[MtB]

1 hour ago, Flyboy said:

It sounds like your accumulator may be over pressurised. What pressure have you pumped it up to ?  I would set it to about 0.2bar (3psi) below the pump cut in pressure.

 

I disagree. Sounds to me as though the accumulator is now spot on. This behaviour is exactly as it should be with a correctly working accumulator.  

 

 

[Tony Brooks]

5 hours ago, Mike the Boilerman said:

 

I disagree. Sounds to me as though the accumulator is now spot on. This behaviour is exactly as it should be with a correctly working accumulator.  

 

 

I agree. Over pressure would give a quicker cut in and cut out time because there is less volume to store water. Just maybe under pressurised but I doubt it.

 

 

[dor]

Sounds exactly the same as mine, and my accumulator is about 30 feet from the pump which is next to the water tank.

[Captain Fizz]

Sounds fine to me too!

[Strettonman]

Thanks everyone. I will leave it as it is. My wife has just reminded me that the previous owner had just replaced the pump before we bought it and it hadnt been used in anger since so maybe the rapid cut in and cut out after turning the tap in and off is not a good reference. 

 

With little previous experience of boats I’m never sure what is ‘normal’ and what isn’t. 

 

Cheers