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National Wood Burner Performance Review: Phase 1

Executive Summary

1 Introduction

2 Methodology

3 Design Verification

4 Conclusions

Appendix 1: Wood Burner Lists for Testing

Appendix 2: Protocol

3 Design Verification

3.1 Results

Table 1 shows the results of the Phase 1 testing in terms of whether the wood burners passed or failed, and the seriousness of any failures. The pass/fail categories provided in Table 1 were developed as part of the protocol (see Appendix 2 for more detail).

Table 1: Summary of Phase 1 review results

Table 2 shows the results of the Phase 1 testing in terms of outcomes (eg, pass first time) at time of writing. Full results for all burners are summarised overleaf in Table 3.

Table 2: Summary of Phase 1 review outcomes

Table 3: Full design verification test results

View full design verification test results (large table).

Although 40 wood burners were selected for design verification (see Appendix 1), a number could not be located or checked in time. Table 4 shows the wood burners that were not located, along with relevant comments.

Table 4: Burners selected but not included in the performance review

3.2 Review follow-up and outcomes

As can be seen from Table 3, 37% of wood burners selected for the review passed the design verification test and 54% failed. The majority of failures were classified as minor. Typical reasons for a minor failure included:

• the compliance label was missing or not specific to New Zealand conditions

• changes to the configuration of the air holes

• changes to the position of the flue.

Follow-up on the identified issues is discussed below.

3.2.1 Dallas Metal Industries Ltd

Table 5: Dallas Metal Industries burners: review results and outcomes

The minor failure identified for the Milan Milano was identified as unique to the prototype inspected, with current sale models consistent with the test report. The project partners were satisfied that the minor faults identified were not representative of the wider population of burners and required no further action.

3.2.2 Hewitsons

The results of Hewitsons burners reviewed are provided below. In accordance with the review protocol, burners with a moderate or serious failure classification were removed from the Ministry web lists of compliant burners. The protocol further requires that burners classified as a serious failure be notified to the Commerce Commission. The Ministry intends to notify the Commerce Commission at completion of Phase 2 of the review.

Table 6: Hewitsons burners: review results and outcomes

* Two different burners with this name were identified in retail outlets in Christchurch (Burner A) and Auckland (Burner B) – see text below.

** Initial (minor) failure was later reclassified as a pass – see text below.

The test engineer encountered serious problems with the Hewitsons Contessa wood burner. This is marketed both with and without an integral water-heating booster, but there are also two alternative performance versions being sold in different parts of the country. Those burners that appear to be sold in the South Island, where the additional compliance with Environment Canterbury and Nelson City Council is required, are being manufactured to a format tested and subsequently approved by those organisations in 2003. However, there are currently versions being sold in the Auckland area that are being manufactured to an earlier configuration tested in 2000 (water heater version) and 2001 (dry version).

This proliferation of models of the Contessa has been further confused by the manufacturer’s more recent change in the name of the wood burner from Contessa EF to Contessa AG. This confusion appears to have extended to the manufacturing process as well, as the two burners apparently assembled to the 2000/2001 format have major variances in key details of secondary air tube sizing. In addition to this, the product labels claimed that the models complied with the NES.

Problems with naming and variance in manufacture were not limited to the Contessa, with similar problems identified for the Bronte and Dante models.

Hewitsons met with the project partners on 9 November 2006. The company then undertook an extensive recall of existing product to remedy the identified faults. At the date of writing, Hewitsons had remedied issues and was awaiting re-verification (ie, completion of a design verification test to confirm that their actions had remedied the faults identified) for the following Bronte Top Outlet AG and Dante burners.

No action was proposed for burners sold since 1 September 2005, the numbers of which remain unknown. The problems with the Contessa remain unresolved.

Lady Kitchener

The minor faults identified on the Lady Kitchener were due to an error in the test report on which the design verification was based. The laboratory reissued the test report and the Lady Kitchener was then independently confirmed as being compliant.

Firenzo Bay and Deco SD Insert

These burners were classed 'undetermined' due to the inability of the test engineer to access the primary air inlets for inspection.

It should be noted that this is deemed an advantage because the lack of ready access to the primary air controls 'fool-proofs' the burner by minimising the likelihood of owners altering the minimum setting. The burners complied in all other respects.

Re-verification of these burners (ie, completion of a design verification test to confirm that the burner matches its test report) is scheduled for the near future.

3.3.3 Lansdowne Research Ltd

Lansdowne Research Ltd holds the authorisation of the Sintes Ethos FS101 burner, which was classified as a minor failure due to a missing label and the inability to access the primary air inlet controls for inspection.

The missing label was identified as unique to the unit inspected, with evidence provided that all current sale models are correctly labelled. The project partners were satisfied that the minor faults identified were not representative of the wider population of burners and required no further action. The overall outcome for this burner was 'resolved'.

3.2.4 Masport / MetalFab Industries Ltd

In late 2006 Masport and MetalFab Industries Ltd were bought out by Glen Dimplex Australasia Ltd. For the purposes of this report, and reflecting the legal title holding authorisation for these burners, the name MetalFab Industries Ltd will be used.

The results of the MetalFab Industries Ltd burners reviewed are provided below. In accordance with the review protocol, burners with a moderate or serious failure classification were removed from the Ministry’s tested and/or authorised web lists of compliant burners. The protocol further requires that burners classified as a serious failure be notified to the Commerce Commission. The Ministry intends to notify the Commerce Commission at completion of Phase 2 of the review.

The Verona inspected was initially classified as a moderate failure due to over double the number of air holes in the secondary inlet tube (67 instead of 33) and a missing compliance label. It later transpired that the model inspected was an older Verona model installed in the shop for heating purposes and not indicative of current production. The project partners were however, concerned that other older models with the same name could be available for sale as there would be no discernible difference to the average consumer.

MetalFab Industries provided assurance that the only Verona models available for purchase were manufactured in accordance with Applied Research Services test report 01/625. The Verona was reinstated to the Ministry’s tested and/or authorised web lists of compliant burners. At the time of writing, re-verification (ie, completion of a design verification test on a Verona available for sale) was scheduled to occur in the near future.

Table 7: MetalFab Industries Ltd burners: review results and outcomes

a This burner was initially classified as a moderate failure but was later reclassified as undetermined. See text below for full details.

b All failures were initially classified as moderate but later upgraded to serious following a delayed response by the manufacturer. This action was in accordance with the protocol agreed to by industry before beginning the review.

c The wetback model could not be located so design verification was carried out on the dry model. This burner is manufactured by Stover Builder International and imported and distributed under licence by MetalFab Industries Ltd.

The Atlanta, Hestia, Micros and Osburn 2200 burners inspected all had significant changes to the configuration of the secondary air inlet to that outlined in the original test reports.

• The Atlanta’s secondary air tube was installed transposed end for end (moderate failure).

• The Hestia’s flue spigot was moved forward 15mm, the primary air inlet opening was increased and the compliance label was missing (three minor failures constitutes a moderate failure). There was also a further undetermined query over a secondary air tube rotated 20° relative to the original test position.

• The Micros had a secondary air tube 25° out of position, there was a 0.5mm increase in hole sizes, the primary air inlet opening was increased, and the compliance label was missing (four minor failures constitute a moderate failure).

• The Osburn 2200’s primary air opening was significantly reduced, the secondary air supply was significantly increased, and the compliance label was insufficient (three minor failures constitute a moderate failure).

As noted above, due to a delayed response by MetalFab these failures were upgraded from moderate to serious.

MetalFab Industries met with the Ministry on 25 October 2006. At this meeting MetalFab queried internal discrepancies in the test report on which the design verification testing is based (differences between the descriptive explanation in the body of the test report and the drawing detail). The queries took just under six months to resolve, after which time MetalFab has undertaken to replace all secondary air tubes in the Atlanta, Hestia and Micros.

Following the initial meeting with the Ministry, the company initiated an internal audit to investigate the cause of the faults with the secondary air tube and to amend production processes to remove the potential for future error. MetalFab also undertook to update all compliance labels on all models available for sale.

MetalFab advised the project partners of the number of Atlanta burners sold since 1 September 2005.⁶ Those still in stock were recalled for repair, but no action was taken on the remaining burners. No information was provided on the number of Hestia or Micros burners sold since 1 September 2005. MetalFab did advise that all Hestia burners available for sale as at 1 January 2007 were undergoing repairs.

At the date of writing MetalFab was awaiting re-verification (ie, completion of a design verification test to confirm that their actions had remedied the faults identified) for the Atlanta, Hestia and Micros burners. With respect to the Osburn 2200, MetalFab advised that a number of in-store units were recalled. No information has been provided on the number of Osburn 2200 burners sold since 1 September 2005, or on any proposed remedial actions.

3.2.5 Pioneer

The Metro Eco, Metro Eco Pioneer Pedestal and Metro Eco Wee Rad were classified as minor failures due to a 13% increase in the primary air plate maximum area and incorrect or missing data on the compliance labels. The increase in primary air controls was deemed to have a minor impact on emissions and/or efficiency by the independent testing engineer.

The Metro Eco Aspire was classified as a minor failure due to missing information on the compliance label.

Table 8: Pioneer burners: review results and outcomes

Pioneer contacted their manufacturer immediately (within a day of notification) to resolve the issue of the primary air intake. They also immediately undertook a review and upgrade of all labels for these models. The company liaised with the project partners on the proposed label amendments and acted swiftly to ensure these were translated into remedies for existing burners in-store. The actions undertaken were clearly documented and evidence provided to the project partners that all 1400 burners in 70 stores were now compliant.

Following this, Pioneer undertook an internal audit and review of all other Pioneer burners. The company is to be commended on their swift and responsive actions in response to the performance review.

3.2.6 Retail Links

Retail Links hold the authorisation for the Jayline Classic, which was classified as a minor failure due to a changed configuration in the primary air inlet and a missing compliance label. It was further noted that the rear edge of the baffle plate was poorly placed and required a form of stop to prevent movement and subsequent bypass of the secondary combustion zone.

Retail Links advised the project partners that there were in fact two versions of the Jayline Classic – a clean-air version that complies with the NES and a non-clean-air version that does not. It appears that verification testing had been carried out on a non-clean-air version, which gave rise to the discrepancies outlined above.

Retail Links acted promptly to notify all stores of the potential for confusion and clarified to the project partners that three stores had both clean-air and non-clean-air versions of the Jayline Classic in stock. The company then undertook to provide clear marketing information so these models were clearly differentiated on the shop floor. They further notified their manufacturer of the need for a clear label for the non-clean-air burners (it is understood that clean-air burners were already correctly labelled). Retail Links then undertook a check of all stores nationwide to audit the point-of-sale tickets placed on all stock. The company further undertook to perform verification on a clean-air burner to demonstrate compliance to the project partners.

The project partners were concerned at the presence of two different models with the same name – a very serious complication that was not anticipated when preparing the review protocol. The project partners requested information on the number of non-clean-air burners currently in stock to better assess the extent of the problem. The partners further requested that all burners be labelled in a unique and identifiable manner, and that this be addressed by 26 November 2006.

Retail Links failed to respond to the project partners, and so, in accordance with the review protocol, the failure of the Jayline Classic was upgraded from minor to moderate. Also in accordance with the protocol, the burner was removed from the Ministry’s web lists of compliant burners in late February 2007.

In April 2007 Retail Links successfully fulfilled all project partner requests, including the re-verification of a (renamed) Jayline Classic CA burner. The burner was immediately reinstated to the Ministry website of authorised burners. The overall outcome for this burner was 'resolved'.

3.2.7 The Fireplace

Table 9: The Fireplace burners: review results and outcomes

Both the Quadra-Fire 2100 Millennium and the Quadra-Fire 4300 Millennium were classified as minor failures due to a decrease in the primary air control opening and missing compliance labels (including serial numbers). The 3.3% decrease in primary air flow was deemed to have a minor impact on emissions and/or efficiency by the independent testing engineer.

Following notification, the Fireplace acted promptly to ensure all stock was labelled correctly.

3.2.8 Tropicair

Table 10: Tropicair burners: review results and outcomes

The Tropicair Kowhai 2000 Mk III was classified as a moderate failure due to the secondary air tube being installed incorrectly (180° out of phase) and a missing compliance label. The Tropicair Tawa Mk IIII (with flue shield) was classified as a minor failure due to discrepancies in the secondary air tube and a missing compliance label.

Tropicair responded immediately by contacting all owners of these burners installed since 2004, checking the models and rectifying any discrepancies with the secondary air tube. The company indicated that the missing labels were due to the models examined being showroom stock only (the company is small and retails direct from the factory showroom) and they have since been rectified. Successful re-verification was carried out on 15 November 2006.

In accordance with the review protocol, the Tropicair Kowhai 2000 Mk III was removed from the Ministry’s web list of compliant burners temporarily, and then reinstated following verification. Tropicair are the only manufacturer in Phase 1 to have acted immediately to rectify issues involving both burners for sale and installed burners. Tropicair are to be commended for their prompt and thorough response.

3.3 General discussion of findings

The response by manufacturers varied significantly. Some were swift to fix identified faults and proactive in their response, whereas others were unresponsive and slow to take action. Delays in remedying identified faults further caused confusion for members of the public considering purchasing burners that were temporarily suspended from the Ministry website. (As an aside, complaints to the Ministry indicate that at least one manufacturer continued to advise potential customers that a suspended burner was compliant when no evidence had been presented to the Ministry to demonstrate this was in fact the case.) We also noted that many manufacturers continued to advertise appliances for sale before authorisation being granted.

In the case of serious non-compliance the protocol developed with industry specified notification to the Commerce Commission. The Ministry intends to notify the Commerce Commission at completion of Phase 2 of the review.

The review revealed a number of issues that were not anticipated during the design of the protocol. These issues offered an opportunity to review and improve the current authorisation procedures carried out by Environment Canterbury and Nelson City Council and the way the Ministry lists burners on its 'tested' and 'authorised' lists.

It rapidly became apparent that the authorisation process plays a vital role in ensuring that wood burners listed on the Ministry website are readily identifiable and compliant with the NES. When the review was undertaken, wood burners could appear on both the tested and authorised lists and were sometimes described differently on each list. This was due to different information being provided to different parties, and it resulted in much confusion.

The fundamental difference between these lists is that wood burners on the tested list have been tested by an approved laboratory, which, on the basis of those test results, provided a certificate to the Ministry that the burner meets the NES. (In some cases, however, the test certificate was based only on an opinion of the laboratory and not a full test. This provides no certainty that the burner was actually compliant.) Wood burners on the authorised list have undergone a more stringent approval process to be specifically approved by organisations such as Nelson City Council or Environment Canterbury. During this approval process, issues such as tamperability have been considered, as well as a physical inspection of the wood burner and a review of all its documentation (eg, installation and operating instructions).

The tested list was initially set up as an interim measure to provide time for manufacturers to obtain authorisation after the NES came into force on 1 September 2005. The problems identified above meant that this interim measure needed to come to an end. Accordingly, the Ministry gave industry six months notice and the tested list was removed on 1 April 2007.

In addition to this, a number of other concerning practices were identified during the review process. On 14 February 2007 the project partners wrote to all New Zealand manufacturers discussing these problems, proposing solutions and inviting comment on the intended approach. Details are provided below (Sections 3.3.1–3.3.2). In addition, Environment Canterbury has undertaken to prepare guidance for applicants. The aim of such guidance is to formalise the documentation and procedural aspects of the authorisation process so applicants are clear about what is required.

It is worth noting at this point that there is no nationally consistent authorisation process per se. Currently, Environment Canterbury and Nelson City Council carry out authorisation individually with a memorandum of understanding for the subset of burners (< 1.0g/kg) authorised by Environment Canterbury that are acceptable to Nelson City Council. The formalisation or adoption of a nationally agreed authorisation process would provide greater transparency to manufacturers and avoid some of the issues encountered during this review.

3.3.1 Proposed improvements to authorisation processes

The following is a list of identified issues and proposed solutions sent to all New Zealand manufacturers in February 2007.⁷

Wood-burner nomenclature

1. Naming consistency

In some cases different variants of a name are being used in different parts of the authorisation application. The application includes the application form, the laboratory test report, the proposed label, the installation instructions, the marketing material and the appliance itself. In one example, five variants of a name appeared on each of the above application documents.

Proposed solution 1a

Require all parts of an application - including the application form, the laboratory test report, the proposed label, the installation instructions, any marketing material and the label on the burner itself - to use the same name. This name will then be used on Environment Canterbury, Nelson City Council and the Ministry websites if the appliance is authorised. Applicants will be asked to achieve this standard before applications are formally receipted and processed. In some cases this will mean applicants have to decide on a name earlier in the process than they have done previously.

Proposed solution 1b

If an appliance is to be marketed under two or more different names, then the proposed procedure applies.

1. The burner and application documents, including test reports, are prepared using one of the proposed names, and the same one on every document. These are submitted and, if successful, the appliance is authorised under this name, with a unique authorisation number.
2. A second set of application documents is prepared, being the application form, proposed label, operating instructions, and any marketing material, but no lab test. Authorisation is sought for this appliance, on the basis of a written assurance from the manufacturer that it is identical to the previous one. Provided the appliance is identical to the one already approved, with only a name change, no further lab test or opinion is required. The appliance can then be authorised under this second name, with a second unique authorisation number, and placed on the relevant website.

2. Different appliances sharing the same name

In some cases we found a 'clean air' version of an appliance sharing the same name as a 'non-clean-air' version, with significant differences in the specifications of key parts of these two versions (such as a low-burn air setting or secondary air supply).

Proposed solution 2

Require a declaration from applicants that the proposed name has not been used for any other wood burner in New Zealand, either currently or in the past.

3. Use of a suffix

In some cases there was a 'generic' name used for a non-clean-air model and the same name plus a suffix for a clean-air model. These suffixes were sometimes complete words (eg, Clean Air), but sometimes just letters or numbers (EF, CA, 165, etc). The obvious concern is that if the suffix is omitted at any point in either the authorisation or consent process it is not clear which appliance is being considered. One solution is to require all appliances using the same 'base' name to have an identifying suffix. Ideally, the suffix would designate compliance (or otherwise) status.

Proposed solution 3

Require a declaration from the applicants that any suffix such as 'clean air' or 'CA' is a part of the unique name, and that any other burner using the same 'base' name shall also have a suffix in all references to that model.

It should be noted that in accordance with Proposal 1a, all advertising material, instruction manuals, etc should similarly be named in a unique and consistent manner with the identifying suffix.

Tolerances

4. Many applications do not provide tolerances on drawings of the appliance

AS/NZS 4013 section 8.2 states that, in relation to the design plans of the appliance, “all dimensions shall be in millimetres and tolerances shall be stated”.

Proposed solution 4

Enforce the requirement in the standard for all applications to include adequate design plans, including dimensions, and tolerances. Then only acknowledge receipt of applications once these drawings and tolerances have been provided. The test report is to be signed by the person who tested the appliance to confirm that the drawings reflect the physical appliance that was tested.

5. Appropriate tolerance designations

Clearly, if a large tolerance is proposed then subsequent appliances built after the original tested appliance could be built with dimensions that are within the stated tolerance, but whose performance is very different to the tested model. AS/NZS 4012 comments on this in note 2 of section 10, which advises:

... manufacturers making a statement of compliance with this … standard … are advised to ensure that such compliance is capable of being verified.

In other words, manufacturers should ensure all examples of a particular model are capable of meeting the requirements of AS/NZS 4013.

Similarly, if a manufacturer claims that a specific appliance meets the NES, then they need to ensure the appliance can achieve 1.5g/kg and 65% efficiency. This means there is a need to ensure the manufacturing tolerances are such that all appliances manufactured are capable of meeting the criteria if tested to AS/NZS 4012 and 4013. Ideally, this would involve having the 'worst case' appliance tested and then, if it passed, assuming that all other appliances manufactured to that specification would also pass. In practice this is problematic, because it is not always obvious what combination of dimensions represents the worst case.

For the purpose of the current performance review, and in the absence of tolerances on most drawings accompanying applications, the following tolerances were used to determine whether a particular appliance could be considered to be the same as that which was originally authorised:

Proposed solution 5a

Authorise only wood burners built within the tolerances specified above. If a manufacturer wishes to produce a line of appliances with a larger tolerance, they may supply a written opinion from the lab that any appliance built to those larger tolerances will still be capable of meeting the criteria (1.5g/kg and 65%). This is likely to require testing of 'worst case' models to support the opinion.

Proposed solution 5b

During compliance verification checks, reject any appliance whose dimensions are outside the tolerances provided with the application for authorisation of the appliance.

3.4 Co-operation from retailers

It was important to the success of this project that retailers co-operated with our engineer. We are pleased to report that retailers were generally most co-operative in this exercise and we would like to acknowledge this.

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