45 Litre Universal Underfloor Fresh Water Tank with Backfill System

This 45-litre universal underfloor fresh water tank is ideal for campervan and motorhome conversions of all types. Designed for flexible installation across a wide range of vans, it provides reliable, discreet fresh water storage without taking up interior space.

Constructed from durable, corrosion-resistant polyethylene, the tank features a matt black finish for a clean and long-lasting underfloor install. Its hygienic, algae-resistant construction ensures dependable performance for long-term van builds.

A large threaded top-mounted access hatch allows you to install pumps, internal accessories or sensors, while providing access for routine cleaning and maintenance.

Water level senders are also available, including options compatible with Victron Energy and SRNE systems.

Fitting Instructions

This universal tank can be installed widthways or lengthways depending on your available underfloor space. Common mounting locations include:

Between chassis members

Beside the fuel tank

Forward of the rear axle

Any underfloor cavity with adequate depth and clearance

For best installation:

The service hatch must face upward.

Ensure sufficient clearance around brake lines, heat shields and the exhaust.

Route the breather pipe high to prevent siphoning.

Mount the backfill system where easily accessible inside the vehicle.

Additional Benefits of the Backfill System

This proven backfill system is widely used across campervan conversions and offers a flexible, user-friendly design. The universal faceplate allows installation without cutting into the van’s exterior bodywork, making it ideal for new builds and retrofits.

Key Advantages

 Can be used as a jet wash supply tank, provided your jet wash can self-prime

 Acts as both a filler and water outlet, so you can empty the tank for winterising without installing a separate drain tap

 Reduces installation complexity by combining multiple functions into a single fitting

  Keeps your van exterior clean and unmodified thanks to the no-cutout design

What’s Included

1 × 45L Water Tank
(Approx. dimensions: 500mm (L) × 400mm (W) × 150mm (H))

1 × 1/2" Elbow for the breather line

 2 × 1/2" Straight Connectors for the blue feed pipe

1 × 1m long 1/2" Breather Pipe

1 × 2m long 1/2" Blue Flexible Water Pipe

1 × Backfill Point with Isolator Valve

4 × Jubilee Clips for securing pipework

1 × Universal Tank/Strap Mounting Kit with fixings

Important Information

Tank may contain traces of water from leak testing—this is normal

Clean the tank thoroughly before first use

 Specifications

 Capacity: 45 litres

Dimensions: 500mm (L) × 400mm (W) × 225mm (H)

Dry Weight: approx. 4kg