So you are about to renovate your existing home, or possibly looking at building a new home.

At some point you will require a BASIX certificate. More than likely you will be required to install a rainwater tank with connection to some garden taps and possibly also connection to toilets and washing machines.

If you are only required to connect the tank to garden taps, then you will only need to purchase a basic Garden Pump which will suffice for this purpose. If however, you do need to connect to fixtures in the home, you are going to need to install a pump system that has some form of “Mains Backup” function.

Obviously when you connect to say a toilet or washing machine, you need to supply a constant flow of water to the fixture. When the fixture is connected to a Rainwater Tank the tank at some point will become empty while it awaits more rainfall. This is where a “Mains Backup” system is required.

There are a number of different types of “Mains Backup” systems available and below we can go through the different options which are available:

Basic Garden Pump with “ Rain Aid “ Float valve

Leader Eco Water Jet Pump ANrainaid

This is one of the most inexpensive systems to install when a simple mains backup system is required. This system is especially popular for “Granny Flat” installations, where the house is single level and may only require one or two garden taps & a toilet to be connected to the tank.

This system is NOT a bypass system like the other Mains Backup systems, and is therefore not the most efficient method in providing mains backup.

Basically the Rain Aid float valve is installed at the top of the tank, and has a mains water feed connected to it. When the tank is empty the float drops down and opens up the valve, allowing mains water to fill the actual tank to a certain set level. You may set the fill level to say 30% of the tank capacity. If you have a 1000 litre tank you could set the Rain Aid valve to keep the tank filled to a minimum of 300 litres at all times.

An example of where this system is not the most efficient is as follows:

Lets say the tank is nearly empty in the morning, and the Rain Aid float valve drops and opens the valve filling the tank with 300 litres of mains water. That afternoon we have a good downpour and the tank is full. You can see from this example that we did not need to fill the tank with the 300 litres of mains water, if we were to wait until that afternoon for the downpour. This is where a By-Pass system is more efficient in water saving.

Manual Valve Manifold System

Manual Valve Mains Backup

As the name implies this system is a manual system, although unlike the float valve system described above, it is a by pass system which does make it much more efficient in saving water.

Essentially the system is made up of interconnecting ball valves and non return valves, together with some unions to allow maintenance if required.

The “Manual Valve Mains Backup” system is extremely reliable as there really are no electronic parts or complicated moving parts, such as solenoids, that could malfunction.

It works by having the valve open which is the feed from tank open together with the middle valve, which is the feed to the fixtures, when there is water in the tank. Of course the mains valve is in the off position while there is water in the tank.

Once the tank is empty, the ball valve from the feed line from the tank needs to be turned off, and the ball valve from the mains feed opened. Until this happens there will be no water been supplied to the fixtures. The obvious downside to this system is that the switch over from Tank to Mains water needs to be done manually.

Imagine its in the middle of the night, and someone in the home needs to use the loo. If the cistern is empty due to no rainwater in the tank, then someone needs to pop outside to do the switchover. This is obviously not a daily chore, its only when the tank is empty. On the other side, once the tank has been filled again with rainwater, the ball valves need to be manually switched back to tank water.

The obvious benefits to this system is that it is less expensive than the automatic options , and generally more reliable, although the downside is the manual operation that is required. Another hidden benefit to the “Manual Valve Manifold” option is that it gives the owner more of an idea how much rainwater / mains water is been used. When you have an automatic mains backup system, generally you don’t really know how long your rainwater lasts you , and if you are on mains or rainwater at any given point in time.

Using the manual system allows the owner to be more involved and aware how efficient his/her Rain Water Tank system is, and how much town water he/she is actually saving.

 

Automatic Hydraulic ” AquaSaver ” Valve

SONY DSC

This hydraulically operated ” AquaSaver ” valve is one or our more popular automatic mains backup solutions for rainwater tanks systems that are connected to the home.

The unit is distributed by Claytech Engineering and can be fitted and operated on any pump that has a auto reset setting within the pump controller. All the Claytech pump units that we sell do come with pump controllers that have this feature, making the AquaSaver valve extremely versatile. It can be used with basic garden pumps or higher end multi-stage pumps.

It is an automatic bypass system, which means when the tank is empty it automatically shuts off the feed from the tank by sensing a pressure drop, and opens up the feed from the mains water. This feed from the mains water pipe bypasses the tank altogether and feeds the fixtures directly. Once there is water in the water tank again, it will be sensed by the auto controller which is on the pump. The pump will turn on again feeding water to the AquaSaver valve, and pushing the spring loaded valve back against the mains water feed shutting it off , and once again feeding the fixtures from the rainwater storage tank. This is all done automatically and does not require anything to be done by the user.

We have found these valves to be extremely reliable and free of maintenance. Claytech does give a 2 Year On Site Warranty which is a major bonuse for new homes or installations. Basically if anything goes wrong in the first two years Claytech will send a technician to your site to rectify the problem or replace the unit. This is of course if the unit has been installed correctly.Image 1

The AquaSaver valve is so reliable as it does not have any electronic solenoids in its constructions and works completely on a mechanical process. This valve unit can be fitted to the top of the external pump itself, or on the wall with bracket supplied. It can also be used with submersible pumps and can be installed on the top of the tank, above where the submersible pump is installed.

In our opinion the AquaSaver option is one of more cost effective, efficient and reliable automatic bypass mains backup pump systems on the market.

The 2 Year On Site Warranty should give purchasers ” Peace of Mind ” , and the fact that it can be fitted to a wide range of both external and submersible pumps makes it an extremely versatile option.