What Strata Committees Should Know About Shared Maintenance for Multi-Head Air Conditioners

Multi-head air conditioning systems are common in apartment complexes, but the maintenance picture is often less clear than the equipment itself. When several indoor units share a single outdoor unit, filter care can become a shared responsibility across owners, tenants, strata managers and building contractors, so it pays to set expectations early.

For strata committees, the goal is not just to keep the system running, but to make sure access, inspection and record keeping are organised in a way that suits the building and the people living in it.

Why shared maintenance needs a clear plan

In a multi-head system, each apartment may have one or more indoor units linked to common plant equipment. That arrangement can create confusion about who is meant to clean or replace the filters, who arranges access, and who keeps the maintenance history.

Without a clear plan, filter care is easy to miss. That can lead to poor airflow, dust build-up on coils and components, and avoidable call-outs when the system does not perform as expected.

A useful strata maintenance plan should set out:

• •which parts of the system are common property and which are within each lot
• •who is responsible for routine inspection and filter care
• •how access to apartments will be arranged
• •who keeps records of inspection dates, filter changes and contractor visits
• •what to do when a unit is leased, vacant or difficult to access

If the building has a strata manager or building manager, they should work with the committee and the mechanical services engineer or building owner to confirm the site’s requirements.

Understanding responsibilities between the lot and the common system

Responsibility is not always obvious just because an air conditioner serves only one apartment. In some buildings, the indoor units sit inside lots but the outdoor unit, pipework or control systems may involve common property or shared services.

That is why committees should avoid assuming maintenance responsibility based only on where a unit is located. Instead, review the scheme documents, building records and any manufacturer information that came with the equipment.

What to clarify early

• •whether filter cleaning or replacement is part of lot owner duties or common property maintenance
• •whether the building manager coordinates access for contractors
• •whether landlords are expected to brief tenants about basic filter care
• •whether any parts of the equipment are hard to reach and need scheduled access
• •whether the system requires a particular filter type, size or rating

If there is uncertainty, it is better to clarify before a problem arises. The committee may also want to keep a note of the relevant equipment models, because replacement filters are not always universal.

If you need the right replacement product, our products page is a useful place to start, and how to measure an air filter explains what details to check before ordering.

Planning access so maintenance can actually happen

Even a simple filter task can become difficult in a strata building if no one has planned how access will work. For apartments, this may involve tenants being at home, notices being issued in advance, or a building manager coordinating keys and contractor entry.

Good access planning reduces delays and helps prevent maintenance from being pushed aside. It also helps when a filter is located behind a return air grille, a ceiling access panel or a joinery installation that is not immediately obvious.

A practical access checklist for committees

• •identify where each indoor unit is located
• •confirm whether access is from inside the apartment or from a common area
• •keep a current contact list for owners, tenants and managing agents
• •decide who can authorise entry for routine maintenance
• •allow enough time for scheduled inspections and any follow-up work
• •note any apartment-specific access issues such as pets, restricted hours or concierge procedures

For larger complexes, it can help to group maintenance visits by level, wing or building section. That makes planning more manageable for the committee and can reduce repeat coordination.

Where maintenance is outsourced, filter servicing or commercial filter servicing may be relevant depending on the property arrangement and the type of system installed.

Record keeping that makes future decisions easier

A good maintenance record is one of the most useful tools a strata committee can have. It helps show what has been inspected, what was replaced, and whether a recurring issue is linked to access, dust load or the wrong filter size.

Records do not need to be complicated, but they should be consistent. Keep them in a central place that the strata manager or authorised committee member can access.

What to record

• •the air conditioner model and location
• •the filter size and product type fitted
• •inspection dates and observations
• •cleaning or replacement work completed
• •contractor details and any recommendations made
• •notes about access problems or damage to grilles and frames
• •any changes to tenancy, ownership or building management contacts

If the site uses pressure gauges or other monitoring devices, record the readings as part of the maintenance history. Pressure drop can help indicate when a filter is loading up with dust, though the right action still depends on the system and the manufacturer’s instructions.

Records are also helpful when ordering replacements, especially if the same building uses several filter sizes across different apartment types. In those situations, custom air filters may be worth considering.

Choosing the right filter approach for a multi-head system

Not every filter task is the same. Some filters are designed to be washable - check the product instructions. Others are intended to be replaced when they reach the end of their serviceable condition. The important point is to use the type specified for the equipment and site conditions.

Where filters are being selected or replaced, the committee or managing agent should confirm:

• •the correct dimensions
• •the filter class or performance level required by the equipment
• •whether the filter is disposable or washable according to the product instructions
• •whether the application calls for a standard item or a made-to-order size
• •whether the installed product is suitable for the local dust load and operating environment

If a building is being upgraded or redesigned, the mechanical services engineer may need to consider the ventilation requirements under AS 1668.2:2024. Site requirements should be confirmed with the mechanical services engineer or building owner rather than assumed.

Standards terminology can be confusing, particularly where older EN 779 classes such as G3, G4 or F5-F9 are still referred to in Australian buildings even though ISO 16890 has superseded that system. MERV, EN 779 and ISO 16890 do not convert directly, so it is best to match the specification used by the equipment or consultant rather than trying to guess an equivalent.

If the building uses higher-efficiency filtration, it is also worth remembering that HEPA ratings are specific. Under EN 1822, H13 is at least 99.95% and H14 is at least 99.995% efficiency at the most penetrating particle size. Those ratings are relevant only where the equipment is designed for that level of filtration.

Making shared maintenance easier for everyone

The best strata arrangements are the ones that reduce uncertainty. When responsibilities are documented, access is planned and records are kept in one place, filter maintenance becomes much easier to manage across the building.

A committee does not need to handle every technical detail itself, but it does need a clear process for who does what, when the work is checked, and how issues are followed up. That approach helps prevent missed maintenance and makes future replacements simpler to organise.

For apartment complexes, it is also sensible to brief new owners and tenants at the start of a tenancy or sale process. A short handover note that explains the system, the access process and the maintenance contact can save a lot of confusion later.

Talk to Total Air Filtration about the right replacement filters

Total Air Filtration is a family-owned air filter manufacturer and supplier in Hillcrest, Brisbane QLD, established 2009. If your strata building needs standard sizes, made-to-order filters or help working out what fits a shared multi-head system, we can help supply or make the right filters for the job.

Call 07 3800 3448 or request a quote. You can also explore our products or get in touch through our contact us page.