Gas Heater Service Checklist: What Should Be Included (and What's Often Skipped)

Updated May 2026 — Around The Clock Plumbing Pty Ltd, Oakleigh South.

Not all gas heater services are equal. A proper annual gas heater service is a methodical safety and performance check that takes 45–90 minutes and produces a written report. A cheap or cursory service may involve little more than a visual look and a filter clean. This guide sets out exactly what should be included in a gas heater service, what cheaper services commonly skip, and how to tell the difference before you book.

What a Proper Gas Heater Service Should Include

A thorough gas heater service — the kind that meets Victorian gas safety standards and gives you genuine assurance heading into winter — covers all of the following:

• Heat exchanger integrity test — checks for cracks that can allow combustion products, including carbon monoxide, to enter the living space. This is the single most important safety check and the one most commonly skipped by cheap services.

• Combustion gas analysis — confirms the heater is burning gas cleanly and efficiently. A heater out of tune produces excess CO even with an intact heat exchanger.

• Flue inspection and flue gas test — checks the flue for blockage, damage and adequate draw to exhaust combustion gases safely.

• Gas pressure check — verifies the appliance is operating within the manufacturer's specified pressure range.

• Burner and ignition inspection — checks the burner for fouling and the ignition system for reliable lighting.

• Thermostat calibration — confirms the thermostat is reading and controlling temperature accurately.

• Filter clean — removes dust and debris from the air intake filter, which affects both efficiency and air quality.

• Written service report — a record of what was checked, what was found, and any recommendations. Essential for rental compliance and useful for insurance purposes.

What Cheaper Services Commonly Skip

The heat exchanger integrity test is the most commonly omitted step in budget services. It takes equipment and time, and a cracked heat exchanger isn't visible to the eye — only a proper test reveals it. Combustion gas analysis is also frequently absent from cheap services, as is the flue gas test. A service that skips these three checks is primarily cosmetic — it cleans the unit but doesn't confirm it is safe.

In August 2025 we serviced a ducted gas heater in Bentleigh that had been 'serviced' by another provider the previous year. Our heat exchanger integrity test identified a crack — a fault that the prior service had either missed or not tested for. The heat exchanger was replaced the same day with a Brivis unit. The homeowner had been running the heater with a compromised heat exchanger for at least one winter season.

What to Ask Before You Book a Gas Heater Service

Before booking any gas heater service, ask the following questions. A reputable gasfitter will answer all of them clearly:

• Do you perform a heat exchanger integrity test? (Not a visual check — a pressure or combustion test.)

• Do you carry out combustion gas analysis and a flue gas test?

• Will I receive a written service report?

• Are you licensed under a Type A gas licence? (Type A covers domestic appliances — Type B is industrial. Confirm BPC licence number.)

ATC Plumbing holds BPC Licence #50694, Type A gas. All our services include every step in the checklist above, and you receive a written report after every job. That's the standard we apply regardless of heater type or age.

How Often Should a Gas Heater Be Serviced?

Annually is the recommended interval for heaters in regular use, and every two years is the legal minimum for rental properties under Victorian tenancy regulations. For heaters that are 10 or more years old, or those that haven't been serviced in several years, a service as soon as possible — before winter — is the right call. Older units are more likely to have heat exchanger deterioration and are less likely to have been inspected properly in recent years.

Fast arrival → accurate diagnosis → permanent fix applies to gas heater servicing too: we don't just service the unit and leave if we find a fault. We diagnose it, explain what we found, and either fix it on the day or give you a clear written recommendation for what's needed.

Common Questions About Gas Heater Servicing

What does a gas heater service checklist cover?

A thorough service covers heat exchanger integrity testing, combustion gas analysis, flue inspection and flue gas test, gas pressure check, burner and ignition inspection, thermostat calibration, filter clean, and a written report. Services that omit heat exchanger testing and combustion analysis are incomplete from a safety standpoint.

Can a gas heater produce carbon monoxide even if it looks fine?

Yes. A cracked heat exchanger or a heater running out of tune can produce elevated carbon monoxide with no visible sign of a problem. The heater may light, heat, and cycle normally. Only combustion gas analysis and a heat exchanger integrity test will confirm CO-safe operation.

How long does a gas heater service take?

A thorough service on a standard ducted or wall heater takes 45–90 minutes. If faults are found and repair parts are required, additional time may be needed — but you'll be given a clear explanation and a fixed-price quote before any repair work proceeds.

Is gas heater servicing required for rental properties?

Yes. Victorian tenancy law requires gas heaters in rental properties to be serviced every two years by a licensed gasfitter, with a record kept. ATC Plumbing provides service records and compliance documentation suitable for property management purposes.

Written and reviewed by Christopher Unwin — founder, Around The Clock Plumbing Pty Ltd, Oakleigh South. BPC Licence #50694, Type A gas, 22 years' experience. National Council member, Master Plumbers Australia & New Zealand.