Weiss heat transfer units recalled

In response to information supplied by the New Zealand Fire Service and Energy Safety New Zealand, Weiss Limited is advising owners of four models of Weiss heat transfer units manufactured before 2010 that it is conducting a voluntary recall of those units.

The affected units are model numbers FV652, FV653, FV 602 and FV 603 manufactured between 2007 and 2009.

A number of these (0.09 percent of the installed base) have been involved in fires and overheating incidents reported to the New Zealand Fire Service between 2009 and 2014. In 2010 Weiss introduced additional safety features into the product.

These newer units, which have a thermal cut out, are not under voluntary recall.

To date Weiss has only been able to inspect two of the units involved in incidents, and neither it nor any of the regulatory authorities have been able to identify a common cause.

While the design of the units complied with the then-relevant standard (ASNZS 3350.2.870), and had been tested, Weiss agrees with Energy Safety New Zealand that there may be a risk in continuing to use these older models.

Weiss has set up an inbound call centre to help people identify whether their unit is affected and will provide advice on recall.

The centre can be contacted on 0800 208 008.

Weiss will also establish a process to ensure that replacement units are properly installed by a registered electrician and are code compliant.

Weiss is also offering all owners of units purchased and installed before January 2010 the opportunity to replace their old unit with a new one with enhanced safety features.

They will be able to purchase it at manufacturing cost (between $138 and $195) and it will be delivered freight free.

Weiss has manufactured and supplied heat transfer units into New Zealand since 2002. Around 20,000 units were sold prior to 2010 and around 35,000 units have been installed in total.

Weiss had been aware of a five incidents that took place between 2009 and 2014.

However, following the publication of a story in the Waikato Times on 19 May, Weiss made inquiries to the New Zealand Fire Service and received information from them, channelled through Energy Safe New Zealand, about an additional 13 incidents.

Weiss has not been able to inspect any units from these other incidents or seen any technical reports.

It received information about them only after coverage appeared in the Waikato Times.

The reasons for overheating and fires cannot be determined with any certainty as there is no clear and consistent evidence of a single common factor.

Potential causes include:
• Failure of the motor driving one of the fans
• Improper installation
• Corrosion in the terminals of the unit
• Improper wiring (not carried out by a registered electrician; not code compliant)
• Damage to the wiring caused by rodent attack
• General wear and tear over time
• Power fluctuations

Given the number and variety of factors that might contribute to the problem Weiss is advising customers to take advantage of the recall offer and install the replacement products using a qualified electrician who can issue a code compliance certificate.

"Any electrical item has to be properly installed and connected by a qualified electrician, certified as code compliant, kept free of obstruction and regularly inspected," says Weiss marketing director, Chris Ahearn.

"This is particularly important if it is installed in the roof area."

"There needs to be at least six metres of ducting between the inlet and the unit, and the ducting should also be no closer than one metre to the flue. The unit should be kept clear of building paper, batts and other insulation materials.

"Further, any electrical device with moving parts should be regularly maintained and inspected. The terminals should be inspected for corrosion and the wiring for rodent damage. This is particularly important if it is installed in a ceiling or other potentially damp area."