All Envireau rainwater harvesting systems utilise four basic elements.These are:
The Controller. The Display. The Sensor. The Filter.

The Controller

The Envireau Rainwater Management System uses sophisticated electronics to control all external system functions.The compact unit (“Direct” and “Gravity”- 290mm x 180mm x 90mm deep,“No Mains”- 240mm x 180mm x 90mm deep) contains all logic conditioning, linear amplifiers for SENSORS,switching relays for SOLENOIDS(s), processing for ALARM indication and DISPLAY,BMS conditioning circuitry, system power supply and FUSE protection.

The power supply is further protected against external faults by a thermal-overload regulator with foldback protection (auto-reset on fault correction). The maximum power consumption for the Controller is 3.5VA (not including PUMP load, see opposite page).The internal control fuse is rated at 250mA. (fitted as standard) which may be replaced with a fuse of the same rating, (Anti-surge) or 500mA, (Quick-blow).The PUMP fuse is rated at 10amp.

Minimum requirement for the cable feed to the CONTROL unit is 2.5mm2 rated at 240v.The electronics and the associated SENSOR and SOLENOID valve, (not used in “No Mains” systems) are located in mechanically separated compartments within the CONTROL unit.This makes the whole enclosure both functionally complete and unobtrusive. All connections, electrical and plumbing are connected to this single unit which makes for exceptionally easy installation and maintenance.

NOTE! EACH rainwater harvesting system requires a mains feed from a separate Residual Current Detector (RCD).

The Filters

The Envireau rainwater harvesting system uses a 3 stage filtration system comprising, the leaf filter, the pump filter and the "In line" filter.

The Leaf Filter

The leaf filter takes out the leaves and grit to ensure that clean water enters the underground holding tank.
The filters vary in size according to roof areas being collected.

The domestic leaf filters for roof areas up to 500m² are housed in their own polyethylene chamber and are available with extension pieces. The filter itself is made from stainless steel and is washable.


The commercial leaf filters are offered in a variety of sizes for roof areas from1200m² - 3350m² they are also made from stainless steel but require a 1200mm diameter chamber in which they are sited. These filters are self cleansing.

The Pump Filter

The pump filter is made from a stainless steel mesh of 220 micron gauge and should be removed annually for cleaning.

The "In line" Filter

This filter has a nylon cartridge of 120 micron gauge and should be washed at 3 monthly intervals. The filter should have an isolating valve on either side to facilitate removal of the cartridge.

The Display Unit

The rainwater harvesting Display Unit is designed to fit neatly to a standard metalclad single socket outlet (which allows for first-fix wiring) and can be surface or flush mounting.Overall size is 85mm x 85mm x 20mm deep.The unit operates on extra low voltage (less than 20v,DC) and is of rigid metal construction with provision for earthing.Connections are made to this item using 4-core 7/0.2mm colour coded cable (considered allowance 1metre, using supplied 6-core cable, see Depth Sensor below).

The Tank Depth Sensor

The DEPTH sensor is a pressure transducer using highly stable thin-film piezo-bridge technology. It is of rugged and durable construction in cast and extruded brass.The SENSOR is capable of resolving water depths as small as +/-2.5mm and is temperature compensated between 0°C and 40°C
Connections to the SENSOR are made via the supplied 6-core cable, (considered length 20metres of which an offcut of excess may be used for the DISPLAY unit above, 2 cores not used).

Underground Storage Tanks

Constructed from GRP, galvanised fixing bracket and 25mm M.D.P.E. tank connector, 110mm diameter inlet.
(Larger diameter inlets and outlets are available on request)