The Grant Spira condensing wood pellet boiler combines easy installation with straightforward operation and low maintenance. Awarded Best Renewable Energy Product 2011 by the SEAI, the Spira utilises our exclusive turbulator baffle system, providing highly efficient, environmentally friendly heating.

Spira condensing wood pellet boiler range

Single units are available in outputs of 5-18kW, 6-26kW and 9-36kW.  The boilers come complete with an adjacent pellet hopper and feed auger, which automatically supplies the Spira with fuel. There is also the option of increasing the output by utilising two boilers (separately flued) and a central hopper/twin auger arrangement. Models include 11-44kW, 12-52kW, 15-62kW and 18-72kW. Using two boilers to achieve higher outputs is very cost effective. When the units are combined their precise electronic burner controls allow both units to modulate as one, down to just 25% of maximum load when the full output is not required. This, combined with the extremely high condensing efficiencies achieved, makes the Spira a unique option when considering a biomass boiler.

MCS LogoThe Spira range was the first condensing biomass boiler in the UK to be eligible for the Renewable Heat Incentive Scheme.

• MCS approved
• Award winning condensing heat exchanger
• DEFRA approved under the Clean Air Act
• Automatic pellet feed and ignition
• Self cleaning heat exchangers and brazier
• Integrated pellet store
• Modulating burner
• Flue box with integral fan/draught stabiliser
• Pellet vacuum systems also available
• Can also be fed from a bulk pellet store

How the Spira works

On start up, the auger feeds the wood pellets into the burner where they are lit by an ignition element. The burner output modulates to achieve the set temperature by controlling the feed rate of pellets. The fan in the burner propels hot gas generated from the fuel into the boiler’s primary heat exchanger. The heat energy is then transferred to the water circulating around the radiators/underfloor pipework of the heating system.

It is important to note that in most modern pellet boilers, up to 20% of the energy that is produced is lost to the atmosphere through waste gases exhausted by the flue system. Grant wood pellet boilers have a unique secondary condensing heat exchanger which has been designed to capture some of this lost latest heat energy so it can maintain extremely high efficiencies.

Siting of appliance

Wood pellet boilers must be installed in damp free environments. The Grant Spira is designed to be sited in a garage, store of outhouse (unless fitted within the Grant SpiraPod which is an outdoor boiler housing for the Spira allowing for external installations).

To enable the boiler to operate safely and efficiently, a correctly sized and permanently open air vent (open to the outside) should be provided in the boiler room. The boilers will carry out an automatic cleaning cycle at pre-set intervals and this process will result in a temporary increase in the noise level so this should be considered when choosing a suitable location. Bulk storage hoppers will require vehicle access for refilling so it is also important to consider where the boiler and its accompanying hopper will be located before purchasing.

Boiler Maintenance

A unique feature of the Grant Condensing Wood Pellet boiler range is that our patented technology results in the boiler requiring very little maintenance compared with other wood pellet appliances. Grant biomass boilers have an automatic self-cleaning system for the primary and secondary heat exchangers to ensure they stay free of debris. They also feature a self-cleaning burner. Using a Grant approved EN Plus Grade A1 wood pellet with low ash content minimises boiler maintenance as larger amounts of pellets can be burned before the ash pan requires emptying which can be up to 2 tonnes in some instances.

Fuel Storage

It is important to ensure that you have sufficient space to store the wood pellet fuel. A bulk storage system can be employed for greater pellet capacity (eg. 4 tonne store) and this be fed directly into the integral boiler hopper supplied as standard with the boiler. Access to larger stores should also be considered to allow for bulk delivery lorries to deliver. It is also worth ascertaining you pellet supplier’s minimum delivery quantity before selecting a store as this could help determine which size store is most appropriate.

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Biomass Boiler Case Studies

Clean and Efficient – Spira gets the thumbs up in Hampshire

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Grant biomass boilers earning their keep for homeowners

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Spira biomass boiler takes residence at Steadings Park in Suffolk

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The social media feeds of Dryad Energy Ltd have been filled with red recently – red Grant Spira biomass (wood pellet) boilers! Dryad Energy has been incredibly busy installing Spira boilers in domestic properties throughout the South with photos from these installs occupying their newsfeeds. We have been speaking toRead More

It is easy being green with a Grant biomass boiler

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Property developer chooses Grant Biomass for new build

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Dual fuel is twice as good

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East Green Energy lead the way with Grant Spira

Renewable energy specialists East Green Energy are leading the way by installing an award wining Grant Spira Wood Pellet Boiler in their showroom at the Company’s Suffolk headquarters. Believed to be the only showroom in East Anglia with a fully working Wood Pellet Boiler, it is certainly generating a greatRead More

Grant Spira biomass boiler cuts fuel bills

A homeowner in Norfolk has noticed an immediate drop in fuel costs following the installation of a 26kW Grant Spira Wood Pellet Boiler by MCS Approved Green Home Energy Solutions. The Spira Wood Pellet biomass Boiler, which replaces an eighteen year old oil fired boiler, will provide heating and hotRead More

Installer promotes advantages of renewable heating

Long established plumbing and heating installers, Great Yarmouth Heating Company Ltd, is promoting the benefits of energy saving, by kitting out their premises with an array of Grant MCS approved renewable technologies. Based on Gapton Hall Industrial Estate, GYH was founded in 1971 and has installed, serviced, and maintained GrantRead More