Venturi VDE Indirect Unvented Cylinder

Available in sizes 80 | 130 | 150 | 175 | 215 | 255 | 305 |400 |500 LITRES

An indirect unvented cylinder for use with a conventional boiler with electric back-up

The Plumbing Group are at the forefront of water heating technology. We are changing the way you think about water heating installations. The Venturi VDE Indirect Unvented Cylinder requires external expansion.

Available in nine sizes ranging from 80 litres through to 500 litres. Our largest model is capable of satisfying the hot water demands of a property with 3 bathrooms and 2 separate shower rooms.

All models are pressure tested to 10 bar and come complete with a temperature and pressure relief valve which is factory set at 7 bar and 90 degrees celsius.

The indirect model comes with 1 immersion as a back-up. This utilises electricity in the instance that your boiler has failed.

Venturi VDE Indirect Unvented Cylinder


Venturi Direct Unvented Cylinder Plan View

Venturi VDE Indirect Unvented Cylinder Heat Loss Performance


Features of a Venturi Indirect Unvented Cylinder

  • 25-Year cylinder and 3-Year parts warranty
  • Sizes 80L to 500L capacity
  • Cylinder manufactured from high grade Duplex stainless steel
  • 60mm fire retardant insulation minimising heat loss
  • 100% CFC/HCFC free
  • Long life with no internal moving parts
  • 3 Bar pressure at outlets
  • All sizes WRAS approved
  • Designed & manufactured in the UK


Venturi VDE Indirect Unvented Cylinder Schematic

Venturi VDE Indirect Schematic


Venturi VDE Indirect Unvented Cylinder Product Construction – Typical

Immersion heater ☞ 3kw, 240V, 1ph, Incoloy 825, with thermostat incl. cut-out
Thermal insulation ☞ CFC/HCFC free, (ODP=0, GWP=1), 60mm fire retardant insulation*
Outer casing ☞ P200 Plastisol
Inner cylinder ☞ Duplex stainless steel
Heating coil ☞ High performance, finned
Indirect thermostat ☞ Twin thermostat with independent reset, 30-70ºC
Safety device ☞ Factory fitted with 7bar/90ºC pressure & temperature relief valve
Connections ☞ Secondary return on 175L & above

*50mm on 400L and 500L vessels

Venturi VDE Indirect Unvented Cylinder Product Specification

Inlet diffuser ☞ For optimal blending of cold & hot water, see fig. 1
Expansion Technology☞  3 bar external expansion
Pressure test☞ Tested to 10 bar
Secondary return☞ Standard fit on models 175L & above
Approvals☞ BBA, CE, WRAS, KIWA, ISO, WRC
Guarantee☞ Internal cylinder 25 years* Ancillary components 1 year
Direct thermostat☞ Element thermostat, nominal setting 60ºC
Indirect model ☞ 22mm diameter stainless steel high performance coil & outlet with 1 immersion heater
Direct model ☞ 80L fitted with 1 immersion heater; 130 – 500L fitted with 2 immersion heaters
Manufacturing ☞ All UK using state-of-the-art robot technology
Horizontal & Slimline ☞ Suitable for roof voids & 450mmØ specification
Renewables range ☞ Solar, heat pump and buffer vessels

*Commercial cylinders carry 5 years guarantee

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