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National Wood Burner Performance Review: Phase 2

Executive Summary

1 Introduction

2 Methodology

3 Test Results

4 Conclusions

Appendix 1: Review Protocol

Appendix 1: Review Protocol

1.0 Compliance verification

1.1 Wood burners that have demonstrated compliance with the current efficiency and emissions requirements of the national environmental standards through testing by a laboratory in accordance with AS/NZS 4012:1999 and AS/NZS 4013:1999 may be required to demonstrate continuing compliance by means of random inspections. The compliance verification will verify that the design, materials and manufacture of a randomly selected production wood burner are not materially changed from the prototype that underwent the efficiency and emissions testing and that the tests undertaken accurately indicate compliance with the national environmental standards.

1.2 Compliance verification shall be conducted on wood burners on the basis of the following three aspects.

• Design verification testing shall be undertaken on a randomly selected number of production units that have current test reports indicating compliance with the national environmental standards, in accordance with the Design Verification Test outlined below.

• Assessment that the emissions test as described in the laboratory test report for the wood burner has been performed in compliance with the test procedure of AS/NZS 4013:1999. Further that the calculation and assessment of emmission levels has been accurately determined in accordance with the test procedure.

• Assessment that the efficiency test as described in the laboratory test report for the wood burner has been performed in compliance with the test procedure of AS/NZS 4012:1999. Further that the calculation and assessment of efficiency has been accurately determined in accordance with the test procedure.

2.0 Design verification test

2.1 Forty wood burners shall be chosen for the design verification test using a statistically valid, random selection. This shall be undertaken by an independent project manager. Wood burners shall be selected from the Ministry published website lists (tested and authorised).

2.2 Production model wood burners selected for the design verification test will be examined for reference against the design, materials, components and assembly of the wood burner that was originally tested to the emissions and efficiency standards.

2.3 The design verification examination shall be carried out by an independent testing engineer, with well-established experience in the field of both general product testing and the manufacture and testing of wood burners.

2.4 Verification examination shall be undertaken on production model wood burners identified and located by the independent testing engineer in accordance with the random selection process.

2.5 Wherever possible, production model wood burners shall be examined in locations away from the point of manufacture, preferably in the premises of a distributor or retailer. Prior to the examination taking place, the agreement of the retailer, distributor or manufacturer shall be obtained from either:

• the retailer, distributor or manufacturer directly; or

• a representative of the retailer, distributor or manufacturer (eg, the New Zealand Home Heating Association).

2.6 Verification examination shall be undertaken at an unspecified time but after 1 May 2006 and before 1 May 2008.

2.7 Compliance with the efficiency and emissions requirements is dependent on many factors in the design, materials and construction of a particular wood burner. Verification that the production model being examined is materially identical to the prototype tested is, therefore, essential.

2.8 Information on the design, materials, components and assembly of the prototype wood burner will be supplied by either the authorising agency or the test laboratory and will include:

i. test reports, including a detailed set of drawings of the prototype wood burner, that were certified by the test laboratory undertaking the efficiency and emissions as being an accurate representation of the design, materials and dimensions of the wood burner

ii. copies of the operating and installation instructions that were available for the prototype

iii. colour photographs of the prototype that were included in the test reports held by the test laboratory.

2.9 Critical parameters in achieving the required efficiency and emissions standards include the arrangement and dimensions of the combustion air systems, the firebox and the heat exchange sector. Verification of a production model wood burner against a prototype tested therefore requires an accurate assessment that the design parameters are within manufacturing tolerances.

2.10 The following construction details require to be measured and assessed against the dimensions and drawings in the test reports certified by the test laboratory undertaking the emissions and efficiency tests, with reference to photographs of the prototype as a cross-check:

2.11 Measurement of dimensions listed in 2.10 shall be undertaken with appropriate measurement equipment with traceable accuracy to national standards:

• dimensions greater than 100 mm – approved make steel rule or certified steel tape

• dimensions up to 100 mm – vernier or digital calliper calibrated against certified gauge blocks or bars.

Hole diameters less than 10 mm using standard set of metric and/or imperial drills, checked against vernier or digital calliper.

2.12 The engineer shall critically examine the appliance against the test documents and photographs of the prototype, and note any obvious changes in the appearance, construction or design or the appliance and its components. The engineer shall accurately record all observations and measurements on a pro-forma test sheet, identifying any measurements that are outside of the agreed tolerances, and return a copy of this with his report to the project manager. The report shall further include an assessment on whether any variations in dimensions or changes in the appliance are significant and likely to vary the previous emissions and efficiency test compliances.

2.13 All details on the attached manufacturer’s identification plate, including manufacturer’s name and address, model and serial number shall be recorded. Where a separate identification plate is attached showing the current compliance certification details, this information shall also be recorded.

2.14 The engineer shall check emissions calculations provided in the test report.

2.15 The engineer shall check efficiency calculations provided in the test report.

2.16 The engineer shall check the heater was tested in accordance with manufacturer’s instructions for the prototype, and whether current instructions contain any information that is contrary to the compliance of the appliance.

2.17 The engineer shall provide interpretation of any design features that may substantially impact upon emissions performance (tamperability, durability, etc).

2.18 Assessment Pass/Fail (refer section 4.0).

3.0 Emissions and efficiency testing

3.1 Ten wood burners shall be chosen for emissions and efficiency testing using a statistically valid, random selection. This shall be undertaken by an independent project manager. Wood burners shall be selected from the Ministry published website lists (tested and authorised).

3.2 Production model wood burners selected for emissions and efficiency testing will be purchased by the programme partners (Environment Canterbury, Nelson City Council) and sent to an accredited testing laborotory for the following tests:

• design verification test in accordance with the protocol outlined in section 2.0

• emissions testing in accordance with AS/NZS 4013:1999

• efficiency testing in accordance with AS/NZS 4012:1999.

3.3 Assessment Pass/Fail (refer section 4.0).

4.0 Review outcomes

4.1 All outcomes will be notified in writing to each manufacturer or distributor on an initially confidential basis (results will eventually be made public).

4.2 Examples of failures are provided in Table 20.

Table 20: Examples of failure

4.3 Failure may be classified in five ways as follows:

(i) Undetermined

(ii) Minor

(iii) Moderate

(iv) Serious

(v) Very serious.

Examples of different types of failure are provided in Table 21. Note that some of the failures compound or build on each other. So, for example, a couple of minor failures may add up to become a moderate failure. Similarly, tested emissions and efficiency results are graduated by where they are in relation to the minimum requirements. A minor failure is one that exceeds the NES and uncertainty of testing, and a very serious failure is defined as emissions above 4.0 g/kg or efficiency below 50 per cent.

Table 21: Example failure classification

4.4 Sanctions, or actions taken following failure, are similarly graduated in response to the severity of failure. Depending upon the outcomes, the following sanctions would apply.

• Pass – the Ministry would prepare a letter notifying success.

• Undetermined – tested emissions or efficiency within uncertainty limits of test method. The Ministry would offer manufacturer an opportunity to retest (at the manufacturer’s expense). Failure to respond to the request would then trigger sanctions for a minor failure.

• Minor failures – the Ministry would prepare a letter notifying the manufacturer of the failure and requesting it be fixed within 1 month. Failure to respond to the request within the month would then trigger sanctions for a moderate failure.

• Moderate failures – the Ministry would prepare a letter notifying the manufacturer of the failure and requesting immediate remedy action. The burner would be ‘suspended’ from published web-based lists until such time as remedy actions can be established to have occurred. Failure to respond to the request within five working days would then trigger sanctions for a serious failure.

• Serious failures – the Ministry would prepare a letter notifying the manufacturer of the failure and requesting immediate remedy action. The burner would be immediately removed from published web-based lists. The Commerce Commission would be notified of misleading advertising (ie, burner being advertised for sale does not meet the standard as claimed), who may choose to prosecute. Failure to respond to the request would then trigger sanctions for a very serious failure.

• Very serious failures – the Ministry would prepare a letter notifying the manufacturer of the failure and requesting immediate remedy action. The burner would be immediately removed from published web-based lists. Notification of the failure would be placed on the published websites and copied by letter to the New Zealand Home Heating Association with a request that all members be notified of the failure. The Commerce Commission would be notified of misleading advertising (ie, burner being advertised for sale does not meet the standard as claimed), who may choose to prosecute. Regional councils may require the fault be remedied in existing installations and may undertake prosecution action.

4.5 Depending upon the nature of the failure, remedy action may take the following forms:

• immediate cessation of production and sales of failed model until fault remedied

• recall of existing product

• repair all burners installed in contradiction of regulatory requirements

• removal and/or replacement of burners installed in contradiction of regulatory requirements.

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