I’ve done something silly with the fresh water pressure system… help!

[James_Calvert]

I've done the give it a suck technique . At the tap. Turn it on first.

 

[Slowtack]

Yep. Fill the tank... Turn on the pump... Suck the tap... Never fails...

 

[Slocumotion]

Same problem with campervan. Same solution. Plus - van had tent/extension with blow-up tubes. The pump with hose attached to the "deflate" nozzle beats sucking.

 

[14K478]

I need a hose that will fit closely over the tap…

 

[PCUK]

Either suck on a tap or use a vacuum cleaner. That will draw the water through. Standard plumbing practice!

 

[MontyMariner]

I would try connecting water hand pump outlet to the tap and try to push some water down to the pressure pump.
That is a common way to remove hot water airlocks in domestic systems (connecting cold tap outlet to hot tap outlet).

 

[vyv_cox]

I would try connecting water hand pump outlet to the tap and try to push some water down to the pressure pump.
That is a common way to remove hot water airlocks in domestic systems (connecting cold tap outlet to hot tap outlet).

That will not work with a typical yacht system that has a positive displacement pump. The valves are effectively NRVs, so water (or air) from downstream cannot pass the pump.
Diaphragm pumps are self priming to a head of a metre or two and cannot airlock unless something very unusual is happening. If the problem still exists I suspect debris in the pump suction valve(s)

 

[Martin_J]

Either suck on a tap or use a vacuum cleaner. That will draw the water through. Standard plumbing practice!

I was wondering why I kept a wet n dry vacuum on board..

You've given me a reason to keep it on board now.

 

[14K478]

Thanks everyone. I havent been able to get to the boat this weekend due to moving house but I will have another go next weekend