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FossilPhill

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In the process of looking for a replacement pump with similar characteristics to the existing pump, I have come across two different brand pumps with similar flow, head, and performance, however, the one claiming the slightly higher performance is a 550 watt motor, and the slightly lesser performing pump is 750 watt motor.
I cannot understand this, as I would think that more power means more water.

The two pumps are as follows:
Lowara (Goulds) XBGR100 750 watts
Hyjet Maxijet HSJ550 550 watts

Lowara 32M of head @ 20 l/m Hyjet 36M of head @ 20 l/m
Lowara 19.9M of head @ 60 l/m Hyjet 21M of head @ 60 l/m
 
Some pumps have a higher service factor than others. Read the pump specs or look at the curve as that is what matters. They sell a ton of those pumps with that flow switch controller on them because they are made to sell and not to last. Get a regular shallow well jet pump with a normal pressure switch/pressure tank and you will be much better off. Adding a Cycle Stop Valve like comes in the PK1A kit would then give strong constant pressure to the house while making the pump last several times longer than normal. That "making the pump last several times longer than normal" is exactly why you see those flow switch control things on pumps that come from the factory and will never see them promote a Cycle Stop Valve.

Sounds like you may not even be in the US. Getting a Cycle Stop Valve shipped to any other country is difficult but we do it all the time.

Shallow Well Pump with PK1A.png
 
Some pumps have a higher service factor than others. Read the pump specs or look at the curve as that is what matters. They sell a ton of those pumps with that flow switch controller on them because they are made to sell and not to last. Get a regular shallow well jet pump with a normal pressure switch/pressure tank and you will be much better off. Adding a Cycle Stop Valve like comes in the PK1A kit would then give strong constant pressure to the house while making the pump last several times longer than normal. That "making the pump last several times longer than normal" is exactly why you see those flow switch control things on pumps that come from the factory and will never see them promote a Cycle Stop Valve.

Sounds like you may not even be in the US. Getting a Cycle Stop Valve shipped to any other country is difficult but we do it all the time.
Thanks for all that information. You are correct, I am in Australia. Having never heard of a cycle stop valve, I will have to do some googling t o find one in Aust. possibly called something else here.
I'm not a fan of the pressure controllers either, so would like to eliminate it is possible, but I have to ask, in the setup pictured, what provides "Run Dry Protection"?
One of the things I don't like about the pressure controllers that I use, is that they seem to be restricting flow to some extent.

My pump setup doesn't supply the house, just the lawns, gardens, few shade houses, and poultry pens, but it also is required to deliver as big a volume of water as possible to our fire hoses if ever needed. Water supply is a 150mm (6") bore, with a 6 metre (20') long 50mm (2") PVC suction pipe.
Draw varies by season, but is 2 to 4 metres.
Due to the reticulation being only L.D. Poly piping, with a max. pressure rating of 43 psi, I have limited options, trying to balance head pressure against flow rates, thus why I run two pumps, one via the pressure controller that came with the pump, the other via a pressure switch, similar to those used on air compressors. It isn't as successful as I had hoped due to it being a mechanical differential switch, with little adjustment. The idea was that the second pump came on only when the pressure dropped sufficiently, then off when pressure increased, but the second pump stays on once tripped in reality.
Due to the way the retic is set out, and the varied purposes it fulfils, the demand varies from a flow of 10 lpm at times, to 90 plus lpm at others.
I'll try to track down a cycle stop valve and have a play with it. :)
 

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That pump can only build 56 PSI max. That limits what you can do with pressure. The one with the flow controller thing on top is not going to stop no matter the pressure until flow stops. Normally I would run a two pump system with just two pressure switches. Staggering the switches turns the highest pressure pump on first, and pump number two only comes on if pump 1 can't keep the pressure up.

The burst pressure of any pipe is 2-5 times the rated pressure. You are also limited by the pipe pressure, but not as much as you think.
 
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