Venturi VHP Heat Pump Twin Coil

Unvented cylinders specifically designed to work with a heat pump

The Plumbing Group has produced an unvented stainless-steel cylinder specifically for use with heat pump applications, providing mains pressure domestic hot water.

Based on the trusted Venturi brand the heat pump cylinder heat exchanger consists of a 28mm finned coil which helps to reduce the pressure loss whilst maximising the heat exchange.

Many heat pumps will not be able to achieve stored water temperature of 60 degrees Celsius, which is necessary to prevent the growth of legionella, all of the Venturi VHP range is equipped with an immersion heater to achieve this.

It is recommended that the thermostat is wired to enable the immersion heater to switch on at a temperature just below the heat pump maximum and then switches off at 65 degrees Celsius. Wiring the Venturi VHP in this manner will reduce the use of direct electricity and will ensure that most of the water heating is achieved through the heat pump.

Venturi VHP Heat Pump Twin Coil

Features of a Venturi VHP Heat Pump Twin Coil Unvented Cylinder

  • 25-Year cylinder and 3-Year parts warranty
  • Sizes 215L 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 VHP Heat Pump Twin Coil 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 VHP Heat Pump Twin Coil 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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