Opus Calypso Wood Burning Boiler Stove


The Opus Calypso Wood Burning Boiler Stove is the UK's first Ecodesign boiler stove that has also been approved by Defra. With energy prices rocketing and showing no signs of slowing down, the Opus Calypso Wood Burning Boiler Stove is being snapped up by an increasing number of urban homeowners keen to cut their energy bills and achieve some energy independence.

A major part of its attraction is that Opus have made it really easy to connect the Opus Calypso Wood Burning Boiler Stove to an existing central heating system. The Opus Calypso comes pre-plumbed with all of the pipework, overheat safety valve, manual air vent and pressure relief valve already in place concealed behind the rear heat shield. Simply connect a load unit (sold separately) and link it in with the existing central heating system using a system zone manifold. There's no need to use a heat exchanger because the Calypso incorporates an over heat quench coil with built in quench valve to prevent the boiler ever over heating. This means that it will work equally well whether it's linked to an open vented or pressurised system provided it is connected to a pumped circuit. Once installed it will help you to reduce the times when you need to run your costly oil or gas system.

The Opus Calypso Wood Burning Boiler Stove has been created specifically for low energy homes where a little heat goes a very long way. The big problem with traditional boiler stoves is that while they are busy providing the hot water for all the radiators and taps they're also pumping out rather more radiant heat from the stove to the living space than is actually needed or is indeed comfortable to live with. Not so with the Opus Calypso, it deliberately has a low heat output to the room to avoid overheating well insulated homes. Depending on the fuel load, heat to the room from the Opus Calypso is both can be as low as just 2.0kW going up to 4.5kW, with a very practical nominal heat output of 3.4kW. Since this heat is mainly convected it will be much kinder to live with and will quickly warm the whole room . Nominal heat output to water is 4.9kW with a heat range of approximately 3.0kW to 6.5kW. That's enough to heat the rooms in most post-2008 homes.

It is common practice when installing a boiler stove in a highly insulated home to feed the boiler directly into a thermal store so that  most of the heat to water produced from the stove (around 60% in the case of the Opus Calypso) can be stored until it is needed. It can then be drawn off as hot water or sent to radiators when it gets particularly cold. This will allow you to use the Calypso as a simple room heater on chilly late spring and early autumn evenings without overheating the rest of the house, particularly the bedrooms.

Apart from sheer practicality, good looks and high efficiency are also part of the Opus Calypso Wood Burning Boiler Stove package. It has a UK-tested A+ efficiency of 83.9%, which is simply amazing for a boiler stove, and will make it very cheap to run. It has attractive tall, cylindrical proportions with an open fronted log store which will easily hold around 12  to 14 logs (more than enough for an evening) and a small Scandinavian style warming plate just above the fire chamber. As you'd expect from a modern stove you get a big air washed window to view the flames and fill your room with firelight. The Calypso's safe distances to combustible materials are impressive too and just about as low as you can get being only 100mm for both the side and the rear. For low energy air tight homes you also get direct external air supply capability as standard. All you have to do is to provide the non-combustible ducting and external grille. The Opus Calypso carries the manufacturer's five-year warranty.

Please Note: Installing a stove that is connected to a central heating system and hot water system must be undertaken by a qualified heating engineer.


Height 1166mm
Width 565mm
Depth 462mm
Weight 172kg
Flue Diameter 150mm
Fuel Wood Burning
Min Heat Output 2kW
Nominal Heat Output 8.3kW
Efficiency 83.90%
Ecodesign Ready Yes
Energy Efficiency Class A
Airwash Yes
Warranty  5 Years
Nominal Output to Water 4.9kW
Nominal Output to Room 3.4kW
Flue Outlet Top
Direct Air Supply Yes
Can Have 12mm Hearth Yes






Opus Calypso Instruction Manual

Opus Brochure


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