DEFRA / Eco Design Ready Guide | Ember's Heating Studio
DEFRA / Eco Design Ready Guide from Ember's Heating Studio

DEFRA / Eco Design Ready Guide

What Is Ecodesign?

In simple terms, the Ecodesign Regulations set new minimum seasonal efficiency and maximum emission requirements for solid fuel burning roomheater stoves, roomheater stoves with boilers and cooker appliances. Only those appliances that have been tested and verified as meeting these new limits will be able to be sold. The emission limits include those for Particulate Matter (PM), Organic Gaseous Compounds (OGC), Carbon Monoxide (CO) and Nitrogen Oxides (NOx).

Implementation dates for Ecodesign legislation in the UK:

  • Independent Boilers – 1st January 2020
  • Roomheater Stoves, Stoves with Boilers & Cookers – 1st January 2022.

The important thing to note is that legacy installations and appliances confirmed to have been placed on the market prior to January 2022 will be unaffected.

So this means, newly manufactured appliances coming off the production line and placed into the supply chain after the 1st of January 2022 will be required to meet Ecodesign legislation requirements. These set new minimum seasonal efficiency and maximum emission limits for all solid fuel appliances. The emission limits relate to:

  • PM – Particulate Matter
  • OGC – Organic Gaseous Compounds
  • CO – Carbon Monoxide
  • NOx – Nitrogen Dioxide.

These are in most cases tested when the appliance is operating at its nominal heat output as prescribed by the manufacturer in their operating instructions. This is the rated output in which the appliance has been designed to operate at by the manufacturer to heat the room in which it has been installed.

DEFRA Exemption

In designated Smoke Control Areas (SCAs), you can burn authorised smokeless fuels in any appliance (as long as the appliance is designed to correctly burn them) or when wanting to burn unauthorised fuels, like wood, you can only do so in an exempt appliance so long as the conditions of the exemption specify the unauthorised fuel (e.g. wood) can be burned. The list of authorised smokeless fuels and exempt appliances can be found on the smoke control website. To find out if you live in an SCA contact your Local Authority.

Exempt appliances are tested at both the nominal and minimum air settings, and they must meet limits for Particulate Matter (PM) emissions in both settings.

Ecodesign legislation will not replace the requirements of Smoke Control Areas and remember to check with your Local Authority to find out if you’re in an SCA.

The risks of slumbering an appliance that is not designed to do so.

Understanding Slumber Mode in Stoves

What is Slumber Mode?

Slumber mode refers to a setting on certain stoves and appliances where the output is purposely reduced to a low or minimum level, typically for overnight use. This mode allows the appliance to continue burning fuel slowly, enabling it to be easily revived in the morning without the need to relight the fire. Some stoves, particularly those burning mineral fuels, are specifically designed to operate in slumber mode and have undergone CE type testing to ensure they are safe for this purpose.

User Beware: The Risks of Slumbering a Stove

While slumber mode can be convenient, it’s important to understand the potential risks associated with running an appliance at low output for extended periods. These risks are particularly pronounced if the stove is not designed for slumbering or if it’s improperly sized for the heating load. When an appliance is too powerful for the space, users may reduce its output to avoid overheating the room, leading to similar issues as those faced with non-slumbering stoves.

Problems Associated with Slumbering a Stove

  1. Incomplete Combustion: Operating a stove at low output can result in incomplete combustion, especially with high volatile fuels like wood logs. This can cause the formation of sooty or dry deposits in the flue, increasing the risk of chimney fires.
  2. Increased Carbon Monoxide and Particulate Emissions: Lower output can lead to higher levels of carbon monoxide and particulates in the exhaust gases, posing health risks and environmental concerns.
  3. Chimney Condensation: Extended periods of low output reduce the temperature in the chimney, increasing the likelihood of condensation. This condensation, combined with acidic flue deposits, can corrode metal components in the flue lining.

Preventive Measures

If regular slumbering is part of your routine, consider using a flue lining system without metallic components to prevent corrosion. When using slumber mode, it’s also essential to follow certain practices to mitigate these risks:

  • High Output Operation: After slumbering, run the stove at a high output to burn away any deposits in the flue and warm up the chimney, improving draught and reducing condensation risks.
  • Avoid Overloading: Never overload your appliance, as this can lead to unsafe operating conditions and exacerbate the problems associated with slumbering.

By understanding and managing these risks, you can enjoy the benefits of slumber mode while maintaining the safety and efficiency of your stove.

The Impact of Slumbering on Flexible Liners

Understanding Flexible Liners

Flexible flue liners are a popular choice for many homeowners due to their ease of installation and replacement. These liners, however, are not intended to last the lifetime of the building. When used correctly, a flexible metal flue liner can last over 10 years, but factors like prolonged slumbering and infrequent chimney sweeping can significantly reduce this lifespan. In some cases, corrosion damage has been known to shorten the life of a flexible liner to less than five years.

The Impact of Slumbering on Flexible Liners

Long periods of slumbering—where an appliance is operated at a low output—can be particularly harmful to flexible metal liners. Slumbering can lead to the accumulation of corrosive condensates and soot deposits within the chimney. These corrosive substances, combined with the lower temperatures associated with slumbering, can aggressively attack the metal lining, leading to premature failure. This not only compromises the safety and efficiency of your chimney but can also void the manufacturer’s warranty on the liner.

Maintenance and Longevity

The efficiency and longevity of any chimney system, whether lined with metal or masonry, depend heavily on proper use and regular maintenance. While masonry and pre-cast chimney systems generally offer greater durability and resistance to corrosion, they often require more intensive installation compared to metallic systems.

Best Practices for Prolonging Chimney Life

To maximize the lifespan of your chimney and its lining, it’s crucial to:

  • Regularly Sweep Your Chimney: Frequent sweeping helps remove harmful deposits before they can cause damage.
  • Avoid Prolonged Slumbering: If you do use slumber mode, ensure that the appliance is periodically run at a higher output to burn off any deposits and warm the chimney sufficiently.
  • Choose the Right Liner: If your appliance will be used in slumber mode regularly, consider opting for a liner system that offers greater resistance to corrosion, particularly non-metallic options.

By following these practices, you can help ensure that your flexible liner, and your entire chimney system, remains safe, efficient, and durable over time.

Carbon Monoxide, Particulates, and the Risks of Slumbering

The Dangers of Prolonged Slumbering

Prolonged use of slumber mode on a stove or appliance can pose serious risks, particularly when the appliance is starved of air for extended periods. When an appliance operates in slumber mode, the reduced airflow leads to incomplete combustion, which significantly increases the production of carbon monoxide (CO) and particulates—both of which are harmful to health.

Increased Risk of Carbon Monoxide Poisoning

The Carbon Monoxide and Gas Detection Society (CoGDEM) has noted that many of the calls they receive on their helpline involve concerns about stoves being left in slumber mode for too long. A particularly dangerous practice is leaving the stove door open while slumbering in an attempt to get extra heat into the room. This not only further increases the levels of carbon monoxide but also allows it to escape more easily into the living space, posing a severe risk of CO poisoning.

Health Implications

Carbon monoxide is a colorless, odorless gas that can be deadly even in small concentrations. Exposure to elevated levels of CO can cause symptoms such as headaches, dizziness, nausea, and in extreme cases, can be fatal. Particulates, on the other hand, contribute to poor indoor air quality and can exacerbate respiratory conditions like asthma.

Best Practices to Minimize Risks

To reduce the risks associated with slumbering:

  • Limit Slumber Mode: Avoid leaving your appliance in slumber mode for extended periods. Instead, operate it at higher outputs when possible to ensure complete combustion.
  • Never Leave the Door Open: Keep the stove door closed while the appliance is in operation to prevent carbon monoxide from escaping into your home.
  • Ensure Proper Ventilation: Make sure your room and chimney are well-ventilated to allow for the safe dispersal of combustion gases.

By following these guidelines, you can minimize the production of carbon monoxide and particulates, keeping your home safe and healthy.