Energy efficiency for gas-fired and oil-fired domestic heating and hot water systems

1. Energy efficiency for gas-fired and oil-fired domestic heating and hot water systems Session 3: Non-condensing and condensing boiler installations, and requirements relating to space heating primary circuits type and design for gas-fired and oil-fired wet heating systems

2. Energy efficiency for gas-fired and oil-fired domestic heating and hot water systemsSession 3 – non-condensing and condensing boiler installations, and requirements relating to space heating primary circuits type and design for gas-fired and oil-fired wet heating systems During the session you will • Familiarise yourselves with the ‘Guide to condensing boiler installation assessment procedure for dwellings’ and associated parameters • Complete calculations relating to boiler installations • Research requirements related to space heating primary circuits types and design for gas-fired and oil-fired wet heating systems • Discuss websites and information you have found Session Objectives and Activities

3. Energy efficiency for gas-fired and oil-fired domestic heating and hot water systemsSession 3 – non-condensing and condensing boiler installations, and requirements relating to space heating primary circuits type and design for gas-fired and oil-fired wet heating systems • Gas-fired and oil-fired domestic central heating must use condensing boilers in most circumstances • Where installation of a condensing boiler may be difficult, an assessment should be completed to see if a non-condensing boiler would be allowed • ‘The Guide to the Condensing Boiler Installation Assessment Procedure for Dwellings’ explains the assessment procedure • If it is suspected that a building may not be suitable for a condensing boiler, a standard form must be completed to assess whether a non-condensing boiler can be fitted for a specified fuel. • Appendix G of Part L of the Building Regulations is the form for assessing when non-condensing boilers are permitted. Introducing the condensing boiler installation assessment procedure for dwellings

4. Energy efficiency for gas-fired and oil-fired domestic heating and hot water systemsSession 3 – non-condensing and condensing boiler installations, and requirements relating to space heating primary circuits type and design for gas-fired and oil-fired wet heating systems The condensing boiler installation assessment procedure for dwellings – assessment criteria • The following criteria must be considered: • Dwelling type • Existing boiler fuel • New boiler fuel • Existing boiler type • Existing boiler position • In the lowest cost option, is the new boiler positioned in a different room from the existing boiler? • New boiler positioned in a different room to the existing boiler? • Extended flue (longer than 2m) necessary? • Condensate pump or soakaway necessary? This will lead to an assessment score.

5. Energy efficiency for gas-fired and oil-fired domestic heating and hot water systemsSession 3 – non-condensing and condensing boiler installations, and requirements relating to space heating primary circuits type and design for gas-fired and oil-fired wet heating systems Circumstances when non-condensing boilers are permitted in domestic heating systems • In residential buildings, a non-condensing boiler is allowed only if: • an existing boiler is being replaced within 3 years of installation under the manufacturer’s or installer’s guarantee • OR • The assessment form shows a score above 1,000 giving evidence that installation of a condensing boiler has been assessed as impractical or uneconomic. • Note that a score above 1,000 does not prohibit installation of a condensing boiler.

6. Energy efficiency for gas-fired and oil-fired domestic heating and hot water systemsSession 3 – non-condensing and condensing boiler installations, and requirements relating to space heating primary circuits type and design for gas-fired and oil-fired wet heating systems Possible difficulties with condensing boilers • There are a number of possible difficulties with installing condensing instead of non-condensing boilers. • Compared to non-condensing boilers, condensing boilers: • discharge gasses from the flue terminal which are cooler, less buoyant and often form a visible plume • discharge gases which may wet surfaces too close to the terminal, or be a nuisance to neighbouring property or people passing nearby • cannot use a flue designed for a non-condensing boiler or share a flue with a non-condensing boiler • form liquid condensate within the boiler which must be discharged to a suitable drain or soakaway

7. Energy efficiency for gas-fired and oil-fired domestic heating and hot water systemsSession 3 – non-condensing and condensing boiler installations, and requirements relating to space heating primary circuits type and design for gas-fired and oil-fired wet heating systems Key websites If you are unsure where to look for regulatory information and guidance, try one or more of the following websites: • UK government Planning Portal www.planningportal.gov.uk • Building and Engineering Services Association (B&ES) www.b-es.org/b-es-connections/technical/ • Energy Saving Trust www.energysavingtrust.org.uk/organisations • Scottish and Northern Ireland Plumbing Employers’ Federation www.snipef.org/ • Welsh Government www.wales.gov.uk/topics/planning • Chartered Institution of Building Services Engineering www.cibse.org Do not feel you must limit your search to these sites if you have ideas of others worth exploring.

8. Energy efficiency for gas-fired and oil-fired domestic heating and hot water systemsSession 3 – non-condensing and condensing boiler installations, and requirements relating to space heating primary circuits type and design for gas-fired and oil-fired wet heating systems From 1st April 2005, revised Approved Document L1 of the Building Regulations sets down revised guidance for the efficiency of hot water central heating gas and oil boilers installed in new and existing dwellings. Appendix G of the revised Approved Document L1 is the Condensing Boiler Installation Assessment Procedure, which is to be used in cases where it is expected to be impractical or too costly to install a condensing boiler. Key points from ‘Guide to condensing boiler installation assessment procedure for dwellings’

9. Energy efficiency for gas-fired and oil-fired domestic heating and hot water systemsSession 3 – non-condensing and condensing boiler installations, and requirements relating to space heating primary circuits type and design for gas-fired and oil-fired wet heating systems You may have found a range of websites that contain relevant information. Note the key websites in your course folder for future reference. Tutor to add specific websites if felt helpful Websites, regulations and standards are frequently updated so you may want to revisit websites and conduct further research in future to ensure you are always using the latest information. Key web pages

10. Energy efficiency for gas-fired and oil-fired domestic heating and hot water systemsSession 3 – non-condensing and condensing boiler installations, and requirements relating to space heating primary circuits type and design for gas-fired and oil-fired wet heating systems Worksheet Students should work individually to complete a heat loss / demand / boiler sizing worksheet with a set of example parameters. Example worksheets are available from various energy providers, manufacturers, trade associations and/or government websites. One example suggested for use in this session is available from The Energy Saving Trust – CE54, available to down load via this link: http://www.energysavingtrust.org.uk/Publications2/Housing-professionals/Heating-systems/Domestic-heating-sizing-method-2010-edition

11. Energy efficiency for gas-fired and oil-fired domestic heating and hot water systems Session 3 Potential Solutions

12. Energy efficiency for gas-fired and oil-fired domestic heating and hot water systems Next session: During the session you will: • Research compliance standards and parameters for hot water storage vessels • Research requirements relating to the preparation and water treatment of hot water systems and wet central heating systems • Research requirements relating to the commissioning of hot water systems and wet central heating systems