About one in five "no hot water" callouts is something the owner could have fixed in two minutes for free. Run the checks for your system type below first.
Triage by system type
| System type | Check first | Then check | Call a plumber if |
|---|---|---|---|
| Gas storage | Pilot light out? Relight per the sticker inside the access panel | Gas isolation valve fully on; other gas appliances working (rules out supply) | Pilot won't stay lit (thermocouple), gas smell, tank leaking |
| Electric storage | Breaker marked hot water or HWS at the switchboard; reset once, wait 2 hours | Off-peak tariff timing (some tanks only heat overnight) | Breaker trips again, water tepid after a full heat cycle, tank leaking |
| Gas continuous flow | Error code on the panel or flashing lights; note the code, try one power-cycle | Gas and water isolation valves fully open; batteries in older ignition units | Error code returns after power-cycle, ignition clicking with no flame |
| Heat pump | Fault code on the display; note it, try one power-cycle at the breaker | Airflow around the unit not blocked; breaker on | Fault code returns, compressor not running, water cold after 24 hours |
| Solar (with booster) | Booster switch on at the switchboard | Days of cloud? The booster should be carrying it; if not, treat as electric or gas fault | Booster on but water still cold, roof leaks or dripping from panels |
One more check for any storage tank: the copper relief valve pipe at the side. Dribbling during heating is normal. Running constantly is a fault that wastes energy and often explains lukewarm water. Lift the easing lever once and let it snap back; if it keeps running, the valve needs replacing.
What's safe to DIY, and what isn't
Fine to do yourself: relighting a pilot light by the printed instructions, resetting a breaker once, checking isolation valves are open, reading an error code, one power-cycle of a continuous flow or heat pump unit.
Licensed work, not DIY: anything involving gas beyond relighting the pilot (gasfitting is licensed work in Queensland and it is illegal and genuinely dangerous to DIY), replacing relief or tempering valves (they are the safety devices that stop scalding and tank over-pressure), electrical elements and thermostats (that's inside the wiring), and anything on a leaking tank. Never cap or tie down a relief valve to stop it dripping. If you smell gas, shut the gas isolation valve and call a plumber; don't keep trying to ignite it.
The two-strike rule: reset or relight once. If the same fault comes straight back, a component has failed and repeating the reset just delays the fix and can cause damage. That's the point to stop and call.
Still no hot water?
If the checks above didn't get it going, the fault is real and it's a repair job. I'm Jieye, licensed plumber and owner of Hills Plumbing & Gas (QBCC 15243081), and most Gold Coast repair calls get a same-day visit with the price confirmed after diagnosis, before any work starts.
Same day hot water repairs, Gold Coast or call 0472 657 042.