Mains water Back-up Box

The Mains water Back-up Box is needed in times of drought as part of your rainwater harvesting system. Every system needs a mains water backup to keepappliances going when there is not enough rainwater stored in your tank

The simplest way is with a float switch and solenoid valve - the float switch detects when the rainwater storage tank is empty and opens the electrically-actuated solenoid valve allowing mains water to flow into the bottom of the tank. When the float switch floats off the bottom of the tank it turns the solenoid valve off and the bulk of the storage tank remains empty ready to admit water from the next rain shower.

Rainwater harvesting plays a large part in reducing the dependence af any building on expensive mains treated water. Toilet flushing, clothes washing and any outdoor use of water can be substantiated by rain water and in most cases the total use of mains water use can be cut in half.</p>

UK Building Regulations require that rainwater cannot possibly flow back into the mains water supply. For this reason all mains backup devices must have an air gap where the mains water flows into the rainwater tank. The easiest way to do this is for the mains water to flow through open air into a funnel shaped device called a tundish (this can be seen in the picture at the bottom right of the unit).

The Mains Backup Box is fitted inside the building where the occupiers can see and hear it. When rainwater has run out, any mains water running from the solenoid valve into the tundish can be seen through the transparent cover and can be heard through the aperture at the side.

The Mains Backup Box replaces a higgle piggle of components with a single wall mounted unit, one electric plug to a wall socket, mains water input and a pipe to the underground storage tank.

Mains Back-up Box Dimensions:

Width - 380 mm
Height - 270 mm
Depth - 95 mm