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Rossluck
27th May 2007, 07:54 PM
Just a friendly warning to anyone buying a water pump for the new rainwater tanks everyone's installing.

On the weekend I replaced a 15 year old Davey pump with a Chinese stainless steel model. After I installed it it started building up to the required pressure, then dropped off, then built it again, and then dropped it. This had me puzzled for ages, and I said to SWMBO that "it's as if the household pressure's dropping off, like there's a leak or something". We checked, no leaks.

To cut a long story short, unlike the Davey pump, the new Chinese one didn't have a built in non-return valve! The pressure the pump built up was being released back through the pump and into the tank.

Non return (or foot valves) are only around $20, and can be installed in the line from the tank to the pump. Problem solved. So if you buy a pump, make sure that you have a non return valve!:D

echnidna
27th May 2007, 08:42 PM
hmmm, might get a check valve

Barry_White
27th May 2007, 09:51 PM
I have a Orange pump that is made in China under licence from Davey. I have a foot valve on it because there is a suction of about 1200mm and a Head of about 8 metres and a run of up to 80 metres now it wouldn't matter what sort of pump you had you would have to have a foot valve on it because that is what is required.

I had an Onga before that was used in the same situation but just wore out but still had the foot valve on it.

I have two other Onga pumps attached to the tanks which are about twenty eight years old. One has a separate non return valve and the other one maybe has an inbuilt non return valve but I can't find it and none of the pumps loses their pressure when they turn off.

I have another pump that is a Davey I use to pump up to the orchard that doesn't have a non return valve or a pressure switch on it that is attached to the tank and I just shut the valve off at the tank and switch off the pump when I am finished watering.

I thought that as a matter of course you always had to fit a non return valve if it was required.