Rainwater Harvesting
Installation of a rainwater system should take account of the local conditions.
Correct design will ensure years of trouble free operation.
Plastic or concrete tank? It is an individual choice whether to use a plastic, GRP or concrete tank. The following issues should be considered:
Where is the rainwater tank situated? Does it need to withstand the weight of people and cars?
Usually concrete tanks are lifted directly from the lorry into the excavation, and therefore suitable access for a lorry to the tank position is needed.
To set a plastic tank you just need 4 strong site workers.
The choice of the filter also depends on local conditions. The schematic diagrams below show.
The choice of the filter also depends on local conditions. The schematic diagrams below show Installation of rainwater filter within a rainwater tank.
Installation of rainwater filter before a rainwater tank.
Different factors influence the location of the rainwater tank:
The position of the tank should ideally be near the control panel room.
Connections from the rainwater down pipes need to be installed at the required gradient.
The outlet to the storm water pipe/drainage system should be accessible.
A sufficient height difference between rainwater inlet and storm water pipe outlet is ideal, so you can select a much lower maintenance rainwater filter, with a steeply inclined sieve surface.
An adequate gradient of the service pipe between the control panel room and storage tank is required. The service pipe contains the cables (pumps, topping up control etc.), the water top up pipe and the rainwater delivery pipe.
Placing a pre-installed hand line (mouse) in the service pipe is recommended.
The service pipe has to be frost resistant, and it should be 0.5 m underground to ensure the water supply for washing machine and toilet in winter.
The service pipe should be sealed to prevent moisture, water and pests from accessing the pipe and its contents.
3P Calmed Inlet
3P Calmed Inlet 125 mm/110 mm Provides a calmed inlet for rainwater in the storage tank. Prevents disturbance of settled sedimentation layer. Made of Polyethylene.
3P Overflow siphon mono
Overflow siphon, with rodent and odour barrier, with skimming effect on tank water surface from chamfered inlet slots.
3P Volume filter VF1 outlet horizontal
Rainwater filter For roof areas to 450 m2. High level of filtering efficiency, independent of flow rate. Continuous filtering of dirt particles. Frost resistant. Self cleaning. Low maintenance intervals Filter insert is easily removed for cleaning. Materials: PE and stainless steel. Stainless steel sieve with a mesh size of 0.55 mm. Height 470 mm. Height difference between inlet and outlet just 300 mm.
» Optional dirt retention basket can be supplied.
1. As water arrives the level builds up and is equally distributed across the cascade
2. Pre cleaning through the cascades. Largest dirt particles are led across the primary filter cascades directly to the sewer.
3. Pre filtered water then flows over the secondary filter sieve (mesh size 0.55 mm). Due to the special mesh structure of the sieve, any dirt washes directly into the sewer which means the filter is self cleaning, with very low maintenance.
4. Cleaned water flows to the cistern. Dirt goes to the sewer