500L, 750L or 1000L: choosing your water tank

Record how much water you use on representative days, including a busy round and any first cleans. Include all operators and note whether a reliable refill is available.

Water demand depends on flow, time actually spent cleaning, technique and the work itself. A tank size cannot guarantee a fixed number of houses or hours. Avoid choosing solely from a description such as “domestic” or “commercial”.

These are water weights, not complete system weights. Obtain the selected equipment’s actual weight and assess the fully loaded vehicle. Check the exact vehicle and axle limits; a model name or “large van” label does not confirm suitability. See GOV.UK vehicle-weight guidance.

Water required = average flow × minutes of active flow × number of simultaneous lines. Use measured values and allow for your actual operating routine.

For illustration only, one line flowing at 2 litres per minute for 180 minutes uses 360 litres. Two lines at that rate for the same time use 720 litres. Driving, setup and breaks do not consume water at that continuous rate unless the flow is left running.

This calculation helps compare capacities; it is not a claim that every cleaner uses 2 litres per minute or that every nominal litre is available in every installation.

• Measure the tank and frame footprint, total height and door openings.
• Check access to filters, the pump, controls and electrical isolation.
• Allow space for reel operation and hose routing.
• Include all other equipment carried in the van.
• Have the mounting and load distribution assessed for the exact installation.

Purpose-made fixing points support a defined installation. They do not make any position or fixing method suitable. Follow the system and vehicle requirements rather than general advice to place a tank near a particular axle.

A tank stores water; it does not purify it. You may fill from an external purified-water supply, use DI treatment or select an RO/DI arrangement. Check that production and refill timing meet the daily demand.

When comparing quotations, separate the tank and frame from pumps, controllers, charging, filtration, reels, hoses and installation. This makes it easier to see which components are included and which you already own.

A larger capacity is worth assessing when records show repeated shortages and the vehicle can support the complete installation. Compare it with a practical refill arrangement or changes that reduce wasted flow.

If changing capacity, confirm which existing components can be reused. Mounting, wiring, pipework and clearances may change; compatibility is not automatic.

Bring your consumption record and vehicle details to System Builder or the Waterworks team to compare a complete specification.