Manual/hand crank water pump to prime shower pump?

[JohnMcClane]

I'm about to replace my shower pump (posted about elsewhere). To ensure the pump is primed I will need to draw the water through it on both feeds.

Last time I took off the shower head, attached a shower hose and sucked the water through.

Is there any type of simple manual water pump (hand crank?) I can buy to make the job easier? I've seen drill attachments, but these say not to run dry for more than a few seconds.

 

[polesapart]

You don't need to prime your pump.*

You do need to ensure that your pump position and pipework layout are exactly in accordance with the pump manufacturers written instructions,where you'll find several acceptable alternatives.



* other than running the shower both hot and cold with the power off on the very first (commissioning) start-up.

 

[JohnMcClane]

* other than running the shower both hot and cold with the power off on the very first (commissioning) start-up.

I've tried that in the past and it doesn't work. I need to draw some water through the pump first or it doesn't work.

 

[Madrab]

I've tried that in the past and it doesn't work. I need to draw some water through the pump first or it doesn't work.

As suggested - There should be at least a small amount of flow through the pump as per it's installation requirements. As long as there is the min flow without the pump running then that should be enough for the pump to prime and then allow the pump to run. Presume it is a standard positive pump and not universal (negative)

If there is no flow through the shower when the pump isn't running then there isn't enough min head, if that's the case then it may have problems in the future with cavitation and that can damage the pump.

You do get pumps that fit onto battery guns that may do what you need.

 

[JohnMcClane]

Thanks. There is flow with the pump turned off, but for some reason once I've introduced air into the system (even the slight amount between the inlet hoses and the pump) it no longer flows.

 

[HERTS P&D]

What shower booster pump do you have? Is it from the 70's?

Andy

 

[Madrab]

Thanks. There is flow with the pump turned off, but for some reason once I've introduced air into the system (even the slight amount between the inlet hoses and the pump) it no longer flows.

Yes, that can happen. If the flow from the cold water cistern (CWSC)/cylinder to the pump is just at the pumps min req, then any air getting in before the pump can be just enough to cause that air to be caught in the pump. That then slows what flow there is down to the point where there isn't enough to activate the pumps flow switch(es).

How high is the CWSC above the shower head it must be at the pumps lower limit?