Searching for HRV filter replacement in NZ leads to different answers depending on which system you actually have. "HRV" is used two ways here: as the name of a specific brand (HRV, a New Zealand company), and as a generic term for any positive pressure ventilation system. The two are not the same thing.
The clearest check is the wall controller in your home. If it carries the HRV brand, this article covers what you need to know. If it shows DVS, you'll find more relevant information in the DVS filter article. If it shows SmartVent, start with the SmartVent filter article instead.
For genuine HRV brand system owners: what follows covers what the filter does, how often to replace it, what the warranty actually requires, and what a proper professional service should include.
HRV is a New Zealand company that manufactures and installs home ventilation systems. The brand name has become so associated with positive pressure ventilation in general that many homeowners use it to describe any system that pushes roof cavity air into the living areas of the house.
This matters for maintenance. Filter grades, service requirements, and warranty conditions differ between brands. A filter specified for an HRV unit is not automatically appropriate for a DVS or SmartVent system.
An HRV positive pressure system draws air from the roof cavity, pulls it through a filter and a fan unit, then pushes it through ducts into ceiling diffusers in the main rooms. The air is not conditioned or exchanged with outside air. The pressure difference created by the incoming air pushes stale indoor air out through natural gaps in the building envelope.
The filter sits inside the fan unit. Its job is to remove dust, pollen, and roof cavity debris before air enters the home. A blocked or degraded filter reduces the volume of air reaching the rooms.
Systems installed before 2014 used a metal or galvanised steel fan box in the roof cavity. These Generation 1 units take an F7-grade filter, held in place with tape.
Systems installed from 2014 onwards use a plastic fan box. Generation 2 units take an F8-grade filter, secured with clips.
HRV's online shop currently sells an F8 filter marketed as compatible with Generation 1, 2, and 3 systems. HRV's published position is that this filter works across all generations.
A NZ trade supplier of compatible filters, the HVAC Shop, takes a different approach. They list a separate F7 product for Generation 1 units and a separate F8 product for Generation 2 units. They do not offer a single filter for both generations.
The underlying engineering principle is well-established. Generation 1 units use fixed-speed fan motors. These motors run at one speed and cannot adjust to compensate for increased airflow resistance. Fitting a higher-grade filter increases the static pressure the motor works against. Over time, that added load affects motor performance. HVAC professionals specify filter grades by equipment generation for exactly this reason.
HRV's published position and the grade-specific approach taken by independent trade suppliers give different answers on this point. Confirming which generation your unit is before ordering a filter is a straightforward step that removes the uncertainty.
Larger homes were occasionally installed with twin-fan units. Each fan requires its own filter.
HRV's published replacement interval for Classic and AirSense positive pressure systems is two years. This appears in their warranty document and on their shop product pages.
There is an inconsistency within HRV's own published material. The AirSense FAQ page on the HRV website states a twelve-month interval. The warranty document states two years. The warranty document is the authoritative source.
Every other major NZ ventilation brand recommends twelve months. The HVAC Shop, which supplies compatible filters for both generations, notes on their product pages that filters last between twelve and twenty-four months depending on the environment, a range that reflects NZ roof cavity conditions rather than a fixed two-year cycle.
HRV's own guidance includes a caveat: environments with higher dust levels may require more frequent changes. Roof cavities in New Zealand accumulate insulation fibres, dust, and seasonal debris. The two-year interval assumes conditions that may not reflect what the filter actually encounters.
Within the five-year warranty period, the HRV warranty document is clear: filter changes must be performed by authorised HRV personnel using genuine HRV filters.
HRV sells genuine replacement filters through their online shop at shop.hrv.co.nz. The Classic filter is $119. The AirSense filter is $139. The product SKU is labelled "DIY."
The product page states that using genuine filters and changing them every two years is required to maintain warranty. It does not state that the work must also be performed by authorised HRV personnel. That requirement only appears in the warranty document itself.
A homeowner reading the product page would see one requirement. The warranty document contains two. The authorised installation requirement and the genuine filter requirement are documented in different places.
One further point: the Classic filter and the AirSense filter are different products. They are not interchangeable.
Once outside the five-year warranty period, the choice of provider and filter is open.
Compatible third-party filters are available from NZ suppliers including Supercell, Filtercorp, and HFS. The filter grade should match the fan unit generation; F7 for Generation 1 metal box units, F8 for Generation 2 plastic box units.
For most homeowners outside the warranty period, the more useful question is who performs the service rather than which filter to source. A full professional service covers considerably more than a filter swap, and the difference matters for how well the system performs. The next section covers what that service should include.
A filter replacement is not a service. A full professional service of an HRV positive pressure system should cover:
The duct inspection is where many services fall short. A partial inspection, conducted only near the fan unit, misses disconnected joints further along the run. Air that bypasses the filter entirely can still reach the ceiling diffusers. The full cavity inspection is what confirms the system is actually delivering filtered air to the rooms. For a detailed breakdown of what professional ventilation servicing covers across all system types, see What does a professional ventilation service include in NZ.
The wall controller is the clearest indicator. HRV brand controllers carry the HRV name and are distinctively branded. If the controller shows DVS, SmartVent, or another name, you have a different brand of system. If the branding is unclear, a technician can inspect the fan unit in the roof cavity to confirm the manufacturer. Getting the brand right matters before ordering any filter or booking any service.
The fan unit itself identifies the generation. Generation 1 units, installed before 2014, have a metal or galvanised steel fan box. Generation 2 units, installed from 2014 onwards, have a plastic fan box. The generation determines which filter grade is appropriate. If you cannot access the roof cavity safely, a technician inspection confirms it.
Within the five-year warranty period, the HRV warranty document requires filter changes to be performed by authorised HRV personnel. The product page on HRV's own shop does not state this condition, but the warranty document does. Self-installation within the warranty period voids the warranty, regardless of which filter is used.
HRV's warranty document states two years for Classic and AirSense systems. The AirSense FAQ page on HRV's website states twelve months. Every other major NZ ventilation brand recommends twelve months. The HVAC Shop, a NZ trade supplier of compatible filters, notes that filters last between twelve and twenty-four months depending on the environment. HRV's own guidance acknowledges that dustier environments may require more frequent changes, which covers the conditions common to most NZ roof cavities.
Genuine HRV filters are sold through shop.hrv.co.nz. The Classic filter is $119 and the AirSense filter is $139. These are different products, confirm which system you have before purchasing. Compatible third-party filters are available from NZ suppliers for post-warranty systems; pricing varies by supplier and grade.
Yes, for systems outside the five-year warranty period. Suppliers including Supercell, Filtercorp, and HFS produce compatible options. The filter grade should match the generation of your fan unit, F7 for Generation 1, F8 for Generation 2.
A full HRV positive pressure service should include: filter replacement at the correct grade, fan housing clean with fan blade inspection, a full ducting inspection across the complete duct run (not only around the fan unit), ceiling diffuser clean in each room, airflow check per room, and a written condition report. A filter swap alone does not constitute a full service.
Outside the five-year warranty period, yes. An independent qualified technician can perform the service using compatible third-party filters. During the warranty period, HRV's warranty document requires authorised HRV personnel to carry out the work.
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