Gas Hot Water Heater: Troubleshooting

Gas water heaters cover about a half of all water heaters that are currently used in households. This ‘umbrella term’ covers three main heater types, gas storage water heaters, instantaneous water heaters and solar water heaters with instantaneous gas boosting. Since the first type is the most prevalent in households, let’s look into some of the common problems so you can quickly identify the issue and have it repaired by a licensed handyman.  

Water’s not hot enough

The hot water issue troubleshooting starts with the thermostat. It might be a clogged flue or vent that’s causing the issue. You can easily learn how to vent your gas heater to keep the vent clear. As it’s a part of the gas valve, a thermostat malfunction may be another possible cause. The third possibility is the dip tube. It’s a long plastic tube that forces the cold water to the bottom of the tank. If damaged or broken off, it will leave you with only lukewarm water.

No hot water at all

If you are not getting any hot water at all, the problem usually lies at the beginning of the system – the gas shut off valve and the pilot light. The pilot light acts as a safety feature for a hot water gas heater, similar to the gas flare stacks used in oil refineries. Not until the pilot is on does the valve let any gas be delivered. If you’re lucky, perhaps the pilot light needs to be relit, which, depending on the type, can be done with a match or its own igniter. If you’re not comfortable doing this yourself, better call a gas maintenance specialist.

Pressure relief valve leak

This valve sometimes vents water, which may look like a leak. There are two reasons for this. First, the tank pressure is too high, which is an emergency that needs immediate attention. Second, the venting valve may be defective, so it vents even when the tank pressure is normal. Since this pressure relief valve is a safety feature, you should definitely call someone licenced, like these emergency plumbing pros from Canberra, to have a look. These guys offer a full range of repair, maintenance, replacement, and installation services for most major brands of gas water heaters.

Pilot unable to ignite

If the pilot won’t stay lit, the usual problem is the thermocouple – a safety device which senses when the pilot light is on and lets the gas valve turn the gas on. While these thermocouples are simple devices, don’t try to repair one yourself. You’re probably facing an hour of a pro’s work and $10 to $15 for the part. A less common problem is a bad gas valve that won’t let any gas reach the burner or the pilot light. However, it the pilot goes on and shuts off the next moment, it’s not the gas valve but possibly a clogged vent.

Dark or rusty water

Water discolouration is caused by a dissolved anode. The anode rod keeps your water tank interior from rusting. They contain aluminium or magnesium alloys that are meant to oxidize in place of the steel in your tank walls. However, as the anode corrodes, it disintegrates up to a point when it can’t perform its sentinel duty anymore – the water starts reacting with the steel and your tank begins to rust. Its lifespan is affected by the hardness of the water and the tank temperature.

The imminent danger of gas heaters is the gas itself. If it’s allowed to escape without being ignited, you risk an explosive situation. Luckily, gas has an artificially added odour so you can easily identify it. While some repairs of gas water heaters are simple, and others may require more work, one thing is certain – they are best left to water heater repair professionals.