Vada water pump

Hi we have a tender with a builder and he has on it a water tank with a Vada pump, are these brands any good?
Cheers

It is a Reece Plumbing pump. Nothing wrong with them but the ones that are supplied are usually too big if you are only supplying a slow filling fixture like a cistern (maximum of 6 litres per minute). You don't want to strangle a big pump. If given a choice, look at a smaller (about 500 W) energy efficient and superior Grundfos pump.

Pump longevity depends a lot on how it is plumbed...one of the common mistakes is to have the tank's outlet valve that supplies the pump fitted too low on the tank. This results in the pump vacuuming sediment, the cause of complaints about dirty cistern water and clogged washing machine filters.

If the pump will also supply an outdoor tap, make sure that the plumber doesn't use tiny flow restricting pipes.

This thread should interest you, the pump was also a Vada.

viewtopic.php?f=35&t=61588

Thanks SaveH20, they haven't said which model number yet so until we get all the paperwork when get the contract we won't know. We will be on rainwater only as no water runs near the block. So I hope that the setup is ok, seems a few people have problems with builders and plumbing and getting it right. Will read that thread. Thanks.

If you are totally reliant on pumped water, I strongly suggest that you invest in a variable speed drive pump. It will cost a lot more but the advantages include a soft start (kinder on the pump and no water hammer), very energy efficient and long pump life.

What would you recommend for average home on tank water. I have Davey pressure pump, its old and getting noisy and the flow is no longer smooth.

If you are totally reliant on harvested water, the pump will have a very hard time as it will need to supply several fixtures when needed yet most of its working life will be low flow demands with minimal run time. This wastes energy and is hard on the pump.

The energy needed to run a centrifugal pump is proportional to the cube of the speed. This means that 75% speed requires 42% full power and 50% speed requires 12.5% full power. It just doesn't make sense to use a big pump to supply low flow fixtures.

A variable Speed Drive (VSD) pump costs more but it delivers constant pressure matched to the demand and energy savings and won't cost much more than buying a large pump with a large pressure tank. For whole house use, a pressure tank's pressure needs to be set high to smooth out the pressure fluctuations when having a shower but it still won't match the constant pressure from a VSD pump.

Grundfos are very good pumps and they also have VSD pumps.

Great information thanks, I will have a good look at Grundfos VSD. I have had Grundfos bore pump for about 8 years now and its been excellent.
My current set up is concrete water tank 25000l and a new plastic tank 10000l, one at either end of the house fed from gutters. I am considering to change to gravity feed for the house. That will mean another tank up the hill and pumping into it from lower tanks. What is the height I would need to equal working VSD pump pressure?

Every 1 metre head = 9.82 kPa but there will be some friction losses depending on the length and size of the pipes and the velocity through those pipes.

Most modern washing machines also have solenoids that have a minimum pressure requirement to operate and this will also have to be known.

You need X4 the head to double the flow rate but doubling a pump's flow rate requires X8 more energy.

It is a bit late once a house has been built but doubling a pipe's true internal diameter increases the volume X4 but if the same head is used, the flow rate increases by approximately X6.

So if the working capacity of the pump is 200kpa I need 20M of head, I dont have that, I think I can only get 10M. ( I will have to see what WM pressure is)
My problem is that if the pump fails or the power is off we can't wash hands or even flush toilet. That is a potential problem for me if I am In Melbourne and have guests in Tas.
Once I built kindergarten with 500l tank on roof as redundancy so kids can have water if supply fails.
I think I will stick with pump set up I have and just buy a new Davey pump and then set up a redundancy gravity feed system to take care of emergency.

The only 3 other alternatives would be to either have a large pressure tank (very expensive), a roof tank that could gravity feed but also operate with a small pump when there was power or else have a solar PV system with battery storage.

At Bunnings I just spotted 12V pressure pump. I will have a look if I can use it to build in redundancy to run off two car batteries and kick in case of power failure. I am interested in off grid solar but have not yet got around to have a serious look. I hope home storage batteries come down in price soon.
I have also spotted $300 constant pressure pump but you get what you pay for.

The 500W Einhell pressure pump that Bunnings stock has a 20 litre pressure tank, a pre pump filter, 2 year warranty, full parts availability and at $299 represents great value. Well worth having a look at.

The pressure tank is set at 20 psi which should draw down slightly more than 6 litres. If you have 6/3 flush cisterns, it should do two 1/2 flushes before the pump starts. If it doesn't quite manage to do two 1/2 flushes without starting, you can simply lower the pressure slightly.

Another alternative is to fit another pressure tank in tandem to increase the draw down. I paid $190 for a 60 litre Pressure Wave tank two years ago but that was a good price...the next best price was $210-220. It has made a huge difference because it is used to supplement an existing pressure tank. I am not sure what the current prices are.

They have given this pump the best chance of having a long life but fitting the filter and pressure tank. Numerous short start/stops on a strangled pump accelerate pump wear but a pump will operate at maximum efficiency when recharging a pressure tank.

Another cause of premature pump wear is when the suction line is fitted to an elbow that is fitted directly to the pump. This is very commonly done. A straight section of suction hose that respects at least 8 diameters should only be connected to the pump.

I mentioned earlier that having the tank's pump draw valve fitted at the very bottom of the tank is another very common mistake...but great if you want to draw the worst quality water in the tank from the sediment layer. I am astounded that so many tanks are plumbed like the one below.