Water Tank Plumbing - push or suck :)

[dazzler]

Hi

Since the great water tank move of 07 I have needed to connect it back up.

We have a system where the water tank feeds into a "Water Bank" that also has a feed from the town supply and if there is water in the tank it uses it first.

The tank is 15m from the waterbank on a fairly level site. The Water Bank is on the wall so overall it needs to raise the water about 800mm. There is a one way valve at the tank to stop water siphoning back into the tank.

So the question.

Should I put the pump near the tank which means it has about a metre of suck and 15m of push or near the Water bank in which case it will suck the 15m.

This is the pump I have;


<TABLE cellSpacing=0 cellPadding=0 width=532 border=0><TBODY><TR><TD style="PADDING-RIGHT: 1 PADDING- 10px" width=458 height=136><TABLE cellSpacing=0 cellPadding=0 width=438 border=0><TBODY><TR><TD>ECOJET R


</TD></TR><TR><TD height=80>Anti-corrosive and rust-proof materials. Motor with thermic overload protection. Double sealing system between motor and hydraulic part. High resistance to frost and icing. Supplied with power cable with plug, switch and self-sealing fitting.

</TD></TR><TR><TD></TD></TR></TBODY></TABLE>


</TD><TD style="PADDING- 10px" width=74 height=136 ;></TD></TR><TR><TD style="PADDING-RIGHT: 1 PADDING- 10px" colSpan=2><TABLE cellSpacing=1 width="100%" border=0><TBODY><TR bgColor=#ebebeb><TD style="PADDING-RIGHT: 1 PADDING- 10px" width=170>Model


</TD><TD style="PADDING-RIGHT: 1 PADDING- 10px" width=167>R 90


</TD><TD style="PADDING-RIGHT: 1 PADDING- 10px" width=167>


</TD></TR><TR><TD style="PADDING- 10px" width=170 bgColor=#f8f8f8>Max. flow (l/1')

</TD><TD style="PADDING- 10px" width=167 bgColor=#fbfbfb>40

</TD><TD style="PADDING- 10px" width=167 bgColor=#fbfbfb>

</TD></TR><TR><TD style="PADDING- 10px" width=170 bgColor=#f8f8f8>Max. head (m)

</TD><TD style="PADDING- 10px" width=167 bgColor=#fbfbfb>38

</TD><TD style="PADDING- 10px" width=167 bgColor=#fbfbfb>

</TD></TR><TR><TD style="PADDING- 10px" width=170 bgColor=#f8f8f8>Rated power w)

</TD><TD style="PADDING- 10px" bgColor=#fbfbfb>600

</TD><TD style="PADDING- 10px" bgColor=#fbfbfb>

</TD></TR></TBODY></TABLE></TD></TR></TBODY></TABLE>

[watson]

G'day Dazzler,
I reckon (given sufficient outlet pipe), that those pumps push better than they suck.

[Skew ChiDAMN!!]

By my understanding, if the piping is of sufficient diameter and the pump/intake pipe is kept below the tank's outlet height, then pump position is a moot argument... I'd simply place the pump in the position that makes for the easiest/safest wiring.

AFAIK it's only where either a section of the inlet pipe or the pump itself raises up above the tank outlet (well... tank water-level, actually, but the outlet is the lowest fixed measurement and would also provide a safety margin) that you need to think about the inlet side at all.

(Oh... or if the pipe is too small a diameter. But then the fix is to resize the piping, not the pump. )

[watson]

What Skew said!

[Brickie]

These types of pumps are made to blow, not suck.

[Skew ChiDAMN!!]

These types of pumps are made to blow, not suck.

True. The head should be on the pump's outlet side.

I'll rephrase what I said to make it a bit clearer: so long as the pump & inlet pipe are lower than the tank outlet, there's no "sucking" involved. Water always runs downhill...

[echnidna]

put the pump near the tank

[Brickie]

True. The head should be on the pump's outlet side.

I'll rephrase what I said to make it a bit clearer: so long as the pump & inlet pipe are lower than the tank outlet, there's no "sucking" involved. Water always runs downhill...

I think youll find the pump will blow the water away from itself quicker than what it can suck it down a long run of pipe, that is unless of course the inlet pipe is massive in size.

Much easier to locate the pump next to the source rather than dick around with pipe sizes..

[Bleedin Thumb]

Sorry have to disagree with you there Skew.

You should always use the shortest inlet run possible, it doesn't matter about the the outlet side as long as the head and pipe diameter meets the pumps specification.

IMHO you never have a setup where you have a long inlet run and short outlet if you want the pump to run efficiently, (unless your pump is lower than your source - which may be the case here?).

In summary you position the pump closest to the water source not "anywhere that is easiest/safest for wireing"

[moonos]

You should always use the shortest inlet run possible, it doesn't matter about the the outlet side as long as the head and pipe diameter meets the pumps specification.

^^ What he said.

Pumps are best put close to the water source. Also, ensure the pump is rated to the discharge head pressure and pipe size, and keep the pump below the inlet water level so there are no priming issues.

I do like the idea of a water tank feeding a bank and switching from tank to mains water IMO, this sort of system should be mandatory on new buildings for laundry, toilets, outside taps as a minimum.

[dazzler]

thanks all

I will put it next to the tank.

I actually feel kinda chuffed. I actually set it up on a concrete base a foot from the tank and level with the base and had the pump ready to be plumbed up to the tank but thought I would check first

The other question is does the pipe from the outlet to the bank have to be copper pipe or is there a more modern solution (noticed the plumbing around the house looked like a poly pipe of some description?

cheers

dazzler

[Timmo]

Two points to keep in mind when sorting out a pump.
1. A pump creates flow, pressure is only caused by resistance to flow ie, gravity or system restrictions.

2.There is no such thing as a suction, merely just a low pressure area which external forces ie gravity, atmospheric pressure push the liquid into the inlet of the pump.

The idea is to make it as easy as possible to let these passive forces move the fluid into the space where it will be mechanically boosted through the pump.

In other words, pump at the tank and let it push the water where it needs to go.

[bricks]

thanks all

I will put it next to the tank.

I actually feel kinda chuffed. I actually set it up on a concrete base a foot from the tank and level with the base and had the pump ready to be plumbed up to the tank but thought I would check first

The other question is does the pipe from the outlet to the bank have to be copper pipe or is there a more modern solution (noticed the plumbing around the house looked like a poly pipe of some description?

cheers

dazzler

Blue line poly is pretty standard, so is pvc pressure pipe. But it's best to try and keep pvc out of the sun because it will deteriorate, and poly will heat up the water so bury it or something.

[ledbe]

Hey!

I am sure there are a lot of contributing factors, pipe size, pump ability, running electrics 15m's. Pump, suck, siphen etc!

Does the water spurt out of the pipe where the pump is near the house when you disconnect the pump? Eg. does the height of the water in the tank create enough pressure naturally?

If theres only one way that water can go ... ?

Ben