Grant ThermaWave Thermal Stores

With rising fuel prices, it is now more important than ever to look for ways to lower home heating costs and save energy. Many people are opting for renewable technologies to heat their homes; however, finding a way of combining several renewable technologies with traditional heating systems has proved very difficult, until now.

Thermal stores allow multiple heat sources to be connected in a number of different ways, with immersion heater(s) back-up. This makes it possible to have a gas or oil fired boiler connected to a solid fuel appliance and also a renewable heat source such as solar thermal or a heat pump. Furthermore, Underfloor Heating system manifolds as well as radiator circuits can also be directly connected to the store.

Grant ThermaWave stores

The Grant ThermaWave is available in three variations:

open-vented with solar coil
open-vented with solar and DHW coils
sealed system with solar and DHW coils.
Sizes range from 250-500 litres.

ThermaWave DHW stores have been designed for situations where there is a greater demand for domestic hot water. The addition of the DHW coil means there is no need to link the store to an additional cylinder, resulting in a more cost effective and compact installation.

A sealed system kit is available to complement existing sealed system products e.g. oil or biomass boiler. Please note, uncontrolled heat sources like solid fuel log burners, must not be used with a sealed system thermal store or unvented cylinder.

Design features

The store has been designed in such a way that it slows inlet water velocities, ensuring multi-level temperature distribution. High specification 1mm thick duplex 2304 Stainless Steel is utilised which resists all forms of corrosion. Compression fittings on most connections dramatically reduces fitting time for the installer and 40mm injected polyurethane foam insulation gives an exceptionally low standing heat loss, making the units highly efficient.

Specification Details

Please note that these product properties are not a replacement for the manufacturer's literature and it is always recommended that Grant Engineering (UK) is consulted before specifying.

Grant Engineering (UK)
Hopton House, Hopton Industrial Estate, Devizes, Wiltshire, SN10 2EU


Grant ThermaWave Thermal Stores

GTHERM/250
• Depth: 580 mm
• Height: 1485 mm
• Thickness: 1 mm
• Weight: 55 kg
• Width: 580 mm
• Energy Efficiency Rating: C
• Water Storage: 250 l
• Uniclass: Pr_60_50 Tank, cylinder and vessel products

GTHERM/300
• Depth: 580 mm
• Height: 1735 mm
• Weight: 61 kg
• Width: 580 mm
• Energy Efficiency Rating: C
• Water Storage: 300 l
• Uniclass: Pr_60_50 Tank, cylinder and vessel products

GTHERM/400
• Depth: 580 mm
• Height: 2110 mm
• Weight: 74 kg
• Width: 580 mm
• Energy Efficiency Rating: C
• Water Storage: 400 l
• Uniclass: Pr_60_50 Tank, cylinder and vessel products

GTHERM300HW
• Depth: 555 mm
• Height: 1650 mm
• Weight: 65 kg
• Width: 555 mm
• Energy Efficiency Rating: C
• Water Storage: 300 l
• Uniclass: Pr_60_50 Tank, cylinder and vessel products

GTHERM300HWU
• Depth: 555 mm
• Height: 1650 mm
• Weight: 65 kg
• Width: 555 mm
• Energy Efficiency Rating: C
• Water Storage: 400 l
• Uniclass: Pr_60_50 Tank, cylinder and vessel products

GTHERM400HW
• Depth: 660 mm
• Height: 1590 mm
• Weight: 80 kg
• Width: 660 mm
• Energy Efficiency Rating: C
• Water Storage: 400 l
• Uniclass: Pr_60_50 Tank, cylinder and vessel products

GTHERM400HWU
• Depth: 660 mm
• Height: 1590 mm
• Weight: 80 kg
• Width: 660 mm
• Energy Efficiency Rating: C
• Water Storage: 400 l
• Uniclass: Pr_60_50 Tank, cylinder and vessel products

GTHERM500HW
• Depth: 660 mm
• Height: 1835 mm
• Weight: 87 kg
• Width: 660 mm
• Energy Efficiency Rating: D
• Water Storage: 500 l
• Uniclass: Pr_60_50 Tank, cylinder and vessel products

GTHERM500HWU
• Depth: 660 mm
• Height: 1835 mm
• Weight: 87 kg
• Width: 660 mm
• Energy Efficiency Rating: D
• Water Storage: 500 l
• Uniclass: Pr_60_50 Tank, cylinder and vessel products

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