Whale Expanse Water Heater, Underfloor, Gas Only

£479.99 (inc VAT) 714.99
BRAND : Whale
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With fast water heat up, reheat and retention, the Whale Expanse is the perfect water heating system to use in a van conversion.

The Whale Expanse Water Heater is an amazing 8-litre water storage solution, perfect for your caravan or motorhome. With a touch of ingenuity, we've designed this product to make the most of your living space. You can conveniently install it under your vehicle if you have room, or inside, using a balanced flue system to offer greater flexibility with placement. This underfloor water heater solidifies Whale's esteemed reputation in heating solutions, with their award-winning space heaters.

The balanced flue feature means you can bid farewell to the days of drilling large holes for flues in your motorhome or campervan. Whale have designed the concentric flue pipes to be directed to the side of your vehicle, hidden under the sill for a neat finish. For those choosing the internally mounted version, the exhaust can be routed through the floor and then to the vehicle's side, using up to two metres of exhaust run.

When installed externally, the Expanse requires only a minimal amount of internal space (214mm x 60mm x 81mm). If fitted internally, you'll enjoy the liberty of setting up hot water without the need to cut holes through your motorhome bodywork.

Experience Rapid Heat Up, Reheat & Retention
Thanks to its highly efficient pre-mixed burner and direct heat exchanger, the Whale Expanse water tank excels in heat transfer. It heats water faster than any other model. You'll have enough hot water for a 14-litre shower in just 11 minutes, and a second shower ready in another 8 minutes - that's 2 showers in just 19 minutes! The water tank is encased in a lightweight plastic outer housing and expanded polystyrene, ensuring efficient insulation and keeping your water hotter for longer.

The Whale Expanse: A Water Heater to suit a variety of situations

The Expanse offers you the choice to run on electric only, gas only, or both combined. Whale also provide a Gas-only model for those who don't need the mains electric option.

Campervan converters will appreciate the freedom to pick from a variety of internal or underfloor chassis mounting locations. The sturdy outer housing includes secure mounting points for a safe installation at the bottom of your vehicle. The Whale Expanse comes with an external gas connection and a built-in fan-assisted flue, which eliminates the need for wall cut-outs. This means your overall vehicle structure stays intact, and your installation time is reduced. The Expanse also features a unique integrated Pressure Relief Drain Valve and an easy connection to Whale Quick Connect 12mm plumbing. We also provide adaptors for all other typical plumbing systems. With the Whale Expanse Water Heater, you're in for a great adventure, made even better with our commitment to ease and efficiency!

Fast Heat Up and Reheat
Hot water for one shower in approx. 11 minutes or two showers in approx. 20 minutes

More Control
Heat water using gas, electric or both for hot water available when you need it.

Winter Protection
Use your van all year round with our user activated frost mode.

Heat Retention
Custom expanded polystyrene ensures that water stays hotter for longer

Whale Van Life Expanse Onboard GE Water Heater Features

  • Fits Internally or Under the floor
  • Balanced flue up to 2 metres long
  • Options of Gas only, Electric only, or combined (Gas only version also available)
  • Selectable 750Watt or 1500Watt power setting
  • Easy to install
  • Space-saving
  • Fast and efficient

What’s Included?

  • 8 Litre Expanse Water Heater
  • Control Panel
  • Coms Cable
  • Flue Kit

Whale Expanse Model Numbers

  • WW0801UC - Underfloor Gas and Electric Water Heater with Whale® Water Heater Control Panel
  • WW0801OC - Onboard Gas and Electric Water Heater with Whale® Water Heater Control Panel
  • WW0821UC - Underfloor Gas Water Heater with Whale® Water Heater Control Panel


  • Water Capacity : 8L
  • L x W x H [mm] : 522 x 262 x 180
  • Weight [kg] : 4.5
  • Cold/Hot Water Connection [mm] : 12mm pipe/12mm stem
  • Gas Type, Pressure [mbar] : Butane/Propane, 30
  • Heat input Gas [kW] 1.35
  • Electric [kW] 0.75 / 1.50
  • Standby Loss [W] Electric – 25 W, G+E – 29 W, Gas – 43 W
  • DC Voltage [V] 9.9 = 12.0 = 15.1
  • DC Current : Operation - 0.48 Standby - 0.03
  • AC Power Supply : 230 V, 50 Hz
  • Max Water Pressure Supply [bar] : 1.9
  • Rated [bar] : 3.0
  • Ingress Protection Rating IP45
  • Max Water Temperature [°C] ~70°C
  • Cylinder Material : Stainless steel 316L
  • Housing Material : PP 20% GF for impact resistance
  • Insulation Material : EPS
  • Certification CE – GAR, LVD, EMC


All products and parts must be installed by engineers who hold a valid certificate of competence. The installation must comply with the manufacturers instructions and local regulations. We cannot be held responsible if these instructions are not followed.

Please note we are a camping, caravan and motorhome company and NO gas product that we sell is suitable for mains (domestic) gas supply.

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If you’ve changed your mind about keeping your purchase, please return it in its original condition with proof of purchase and we’ll exchange or refund it. Unless faulty, this should be within 30 days of receiving your order. By original condition, we’d expect this to mean that you’ve kept packaging and labels, and that the item is undamaged and unused.

For further information of how to return your item, please visit the "Returning an Unwanted/Faulty/Damaged Item" section on our Help Page.