Introducing the RainForce Home Mains Water Top-up Kit from 3P Technik UK. The RainForce ensures that you can continue to flush your toilets, wash vehicles and keep washing machines running come rain or shine!

It’s a great feeling to have a Rainwater harvesting system installed for your home. All that free rainwater to use whenever you need it. During dry summers however, you can quickly wish you were back on mains water so you don't have to worry about flushing the toilets or carrying heavy buckets of water around the house.

We wanted to share a smart upgrade: the RainForce Home from 3P Technik UK. It’s an easy to install back up for periods of low rain. This intelligent mains water top-up controller kit automatically senses when your tank drops below a set level and precisely adds enough mains water  to keep toilets, washing machines, or garden irrigation running smoothly—even during dry spells. Unlike traditional float switches, it uses a durable, solid state conductivity probe to detect water levels which enables the Control unit to also detect leaks and alert you if a problem arises—meaning no water waste, and no guesswork for you.

How the 3P RainForce Home Mains Water Top-up Controller Works

When your stored rainwater falls below your chosen threshold, the stainless-steel sensor (installed in your rainwater tank) signals the solenoid valve to open briefly, topping up the tank until the probe is covered—and it even continues for a period that you can define to prevent short cycling and protect your pump. Safety is built in too: the tundish ensures a compliant air gap to prevent back flow, and the controller can even isolate the pump to avoid any possibility of it running dry during the refill cycle (this is highly desirable if your pump pumps out water faster than your mains water pipes will allow into the tank).

The RainForce Home is a robust, low maintenance solution for domestic systems. It has built-in leak alerts, solid-state sensors, effortless reliability and zero guesswork.

Ready to Upgrade your Domestic Rainwater Harvesting System?

If you’re interested in ensuring reliable operation, minimising mains water usage, and protecting your system’s components, we’d love to help you explore whether the RainForce Home is right for your rainwater harvesting system. You can read more about it on the RainForce Home page. We also have Mains water Top-up Controllers for Commercial systems and Indirect systems, just contact us if you would like to talk through the options. Our friendly technical team are here to help.

Keeping your rainwater system flowing shouldn’t be a worry—let’s make it effortless together