Improve Gravity Fed Mixer Shower Pump Pressure?

[DC4_DIY]

Hello All,

I believe that some time ago I may have replaced the Shower Pump that stopped working after approximately 3 to 5 years or more with the wrong Shower Head Pump type.

The Shower is Gravity Fed from the Cold Water Tank in the Loft above the Bathroom where the Hot Water Tank is within the Airing Cupboard next to the Bath.

When reviewing the Bristan [Varispeed Water Pump 50] Installation Instructions I assumed that this Pump would work ok because the shower head was more than 230mm below the bottom of the Cold Feed Tank as stated within the Instructions.

I believe that I may be correct to assume that the pump we currently have is a Positive Head type.

This being due to the fact that the Installations Instruction and User Guide has a Negative Head Option Kit, that was not included with the pump, and the method shown of how the Negative Head Kit is installed with a Pull Cord Switch.
> With this being said is there any way of knowing from just looking at and running a shower pump if it is a Positive or Negative head shower pump?

When searching on Google for water pressure of the Bristan - Varispeed Water Pump 50, I believe that I have found it to be only 1.5 Bar.
I can 100% confirm that it is not written within the instructions and user manual.
And I do not recall seeing a Bar Rating on the side of the Pump to know for sure.

Unfortunately our TRITON, Capella, Thermostatic Mixer Shower has a very poor pressure that will only start with both the Hot and Cold when the Shower Head is at waist height.

If I were to change the current Bristan Shower Pump to a known Negative Head Shower Pump will my Wife and I get and feel a shower with a notably higher improved pressure from the Gravity Fed Cold and Hot Water Tank the Shower Pump sits next to on the floor within the Airing Cupboard?

The poor pressure may also be down to the cost of the Pump when I bought it?

It may have been in a Sale or I just thought it was good value for money...

Unfortunately this Shower has never had the pressure expected in comparison to Hotels for example:-(

Moving forward from what I have read if I were to change the Shower Pump I think that I would invest in a Centrifugal Negative Head Shower Pump.

> Centrifugal - Better Quality than a Regenerative Pump and Quieter.
> Negative - Assumed to be for improved pressure.
> The Shower Head is within 600mm from the bottom of the Cold Water Tank above.
> Ergo; A Negative Head Shower Pump is required - TBC?

Please do not hesitate to ask any questions for clarification on anything mentioned or not mentioned.

Thank you in advance, I will look forward to your feedback.

I trust that you will continue to be safe and well during this current pandemic Coronavirus uncertainty.

A video clip of the Shower Flow with and without the Mixer can be sent for review upon request.

Thanks,

Daniel > DC4 DIY

 

[Jeff Handy]

I don’t think many forum members will have experience with this European style of plumbing setup.

Most members are in North America.

But you might get lucky!

 

[breplum]

Jeff, I just looked it up; negative head shower pump. Interesting but nothing we've ever seen in the USA.
each side has a suction and a discharge. Fascinating but no desire to dig deeper.

 

[Jeff Handy]

It looks like a cute little robot.

 

[DC4_DIY]

Hello Again Breplum and Jeff Hardy,

Please accept my apologies for the delay with my reply to your response to my question posted.

I trust that you had a great Christmas 2020, and will have a prosperous New Year 2021, despite the Coronavirus Pandemic restrictions.

Moving Forward; I may have been fortunate enough to have resolved to plumbing issues at once.

Both the Bath Tap and Hot Shower Pump feeds share the Hot Water Cylinder outlet pipe.

A few months ago we had our loft insulated with spray foam insulation.
With the assumption that the open top Cold Water Header Tank was covered to stop any debris falling in to it.

After removing the flexible hose to the Bath Hot Water Tap and finding no debris or corrosion, by pulling a ‘J Cloth’ through it, I choose to check the Hot Water feed to the Shower Pump.

Fortunately for me and the Kitchen Ceiling below, I did have a towel to catch the water within the pipe and the Black Bits Debris.

It is assumed that the Black Bits Debris were from the Cold Header Tank via the Hot Water Cylinder.

Following this I removed all of the pipes from the Shower Pump, to find that there was some Debris within the Hot Water Feed Filter.

After cleaning the filter and re-connection of the Hot Water Pipes for the Bath and Shower Pump, there were no more Black Bits coming in to the Hot Tap in to the Bath.

And with about a 90 Degree Turn of the Shower Pump Boost Dial the Shower Pressure has been increased enough to know that you are having a shower…

(For Details Please See Other Thread; How To Stop Hot Water Tap Black Bits Debris?).

Please be Safe and Well during this Coronavirus Pandemic uncertainty.

Thank You in advance for your feedback.

Kind Regards,

Daniel > DC4_DIY