Gas Heater Not Working? Melbourne Troubleshooting Guide

Gas Heater Not Working? Start Here

Before calling a plumber, there are a few things worth checking yourself — they resolve the problem more often than you'd think. Work through these in order.

Step 1 — Check the Gas Supply

Check whether other gas appliances in your home are working — the stove, another heater, or the hot water system. If nothing gas-powered is working, the issue may be with the gas supply to the property rather than the heater itself. Contact your gas supplier (in Victoria, usually Multinet Gas or Australian Gas Networks) before calling a plumber.

Step 2 — Check the Thermostat

Make sure the thermostat is set above the current room temperature. For battery-powered thermostats, replace the batteries — low batteries are a surprisingly common cause of a heater appearing completely dead. For smart thermostats, check it hasn't lost its Wi-Fi connection or reset to a factory schedule.

Step 3 — Check the Return Air Filter

A clogged return air filter causes the heat exchanger to overheat and the heater to shut down on its safety limit switch. Locate your return air grille — usually a large louvred panel in the hallway ceiling or wall — and check if the filter is clogged with dust. If so, clean or replace it and try again.

Step 4 — Look for a Fault Code

Modern gas heaters display fault codes on their digital panel when they shut down due to an internal fault. Note the code number and check your user manual. Common codes relate to ignition failure, flame sensor faults, or pressure switch issues. These almost always require a licensed gas fitter.

Step 5 — Pilot Light (Older Heaters)

If your heater has a standing pilot light, check whether it has gone out. Your user manual will have relighting instructions — typically holding a reset button while lighting the pilot. If it won't stay lit after several attempts, the thermocouple has likely failed. This is a quick and inexpensive repair for a licensed gas fitter.

If none of these resolve the problem, call ATC Plumbing on 1300 282 758. We carry out gas heater repairs across Melbourne's south-east under BPC Licence #50694.