Fresh Water Pump

[pearley]

Our old boat had a FloJet water pump which gave up to 12.5 litres/minute at 35 psi which gave a good shower through a large rain shower head.

 

New boat has Parmax with 11 litres/minute at 25 psi which gives a pathetic shower. The cold water from tank to shower is about the same, the hot had to travel almost twice as much.

 

I have a spare FloJet so is there any reason, other than size difference, why I can't substitute it? Or buy a higher pressure, higher flow Parmax with same footprint?

[Tony Brooks]

It will be fine as long as your calorifier PRV is at least 5 psi higher rated than the pump cut out pressure. Do you have  a water economy shower head fitted? Does the pump cycle while you shower, if yes then another pump may not make any difference apart from to the cycling rate.

 

Some showers have a restrictor in one of the hose unions, have you taken it out?

[pearley]

PRV is the 4 Bar one fitted by Surecal. Pump on old and new do not have accumulators so pump running all the time after residual pressure in the system had gone. Shower head came with 2 restrictors. It has the larger flow one fitted.

It is one of those shower heads that mix air in with the water. It has 4 settings but pretty poor on all.

Edited June 11, 2021 by pearley

[Tony Brooks]

10 minutes ago, pearley said:

PRV is the 4 Bar one fitted by Surecal. Pump on old and new do not have accumulators so pump running all the time after residual pressure in the system had gone. Shower head came with 2 restrictors. It has the larger flow one fitted.

It is one of those shower heads that mix air in with the water. It has 4 settings but pretty poor on all.

 

So a water economy shower head. I would try a cheap  new one.

 

If the pump runs all the time a higher output one should help.

Edited June 11, 2021 by Tony Brooks

[pearley]

Boat came with a cheap shower head but was no different.

 

Will try it with my spare pump when I can find what box it's in.

[ditchcrawler]

Just now, pearley said:

Boat came with a cheap shower head but was no different.

 

Will try it with my spare pump when I can find what box it's in.

You could measure how much water is coming out of the shower, just run it into a bucket for 2 minutes.

[pearley]

Just now, ditchcrawler said:

You could measure how much water is coming out of the shower, just run it into a bucket for 2 minutes.

On my list of things to try. Easy enough to measure 11 litres a minute.

[ditchcrawler]

1 hour ago, pearley said:

On my list of things to try. Easy enough to measure 11 litres a minute.

I would suggest trying with the shower, with the shower head removed and from a tap open full bore