You found water near the water heater, and now the pilot won't stay lit — or won't light at all. Those two events are almost certainly related: water and pilot assemblies are natural enemies. Here's what the dead pilot is telling you, what's safe to check, and when the right move is a professional instead of a match.
Here's how to think about it like a technician — and the routine that keeps you ahead of it.
How a leak puts out a pilot
It doesn't take much. Water dripping onto the burner assembly can simply drown the pilot flame; steam from water hitting hot surfaces can snuff it too. Even a small, steady drip aimed at the wrong spot will win against a pilot light eventually.
The sneakier version is indirect: water corrodes the pilot orifice or the thermocouple connection over days, and the pilot that lit fine on Monday won't stay lit by Friday. Either way, the leak came first — the pilot is the symptom.
Water damage to the thermocouple
The thermocouple is the little sensor that tells the gas valve 'yes, there's a flame, keep the gas on.' Water exposure corrodes it or its connection, and a compromised thermocouple can't hold the gas valve open — so the pilot lights, then dies the moment you release the button.
This is the most common 'pilot won't stay lit after a leak' story we see. The part is inexpensive; the diagnosis — confirming it's the thermocouple and not the gas valve — is the skilled part.
Why relighting sometimes fails
If water is still reaching the burner area, relighting is mopping while the tap runs — the pilot will just die again. And if the thermocouple or gas control is water-damaged, no amount of careful relighting technique will overcome a part that can't do its job.
There's also the case where the pilot lights but the main burner behaves badly — yellow, lazy flames or rollout — which means the burner itself took water damage. That's a stop-and-call-a-professional situation, not a try-harder one.
Safety before relighting
First, the leak: is the water source fixed and the area dry? Relighting into an active drip is pointless. Second, sniff for gas — if you smell it, stop, don't touch electrical switches, and call for help from outside the home.
Third, look at the burner compartment with a flashlight: heavy rust, standing water, or white/green corrosion on the gas controls all mean hands off. A clean, dry compartment with an intact pilot assembly is the only scenario where a careful relight attempt is reasonable.
When the gas control valve needs replacing
Gas control valves don't tolerate water. If the valve body or its connections got wet — especially repeatedly — internal corrosion can make it stick, leak gas, or fail to regulate. This isn't a clean-and-dry fix; manufacturers and codes treat a wet gas valve as a replace-don't-repair part.
We'll say it plainly: a water-damaged gas valve is not a DIY judgment call. If there's any chance water reached it, a professional needs to inspect and usually replace it before the unit goes back into service.
DIY relight vs. professional diagnosis
Reasonable DIY: the area is dry, the leak is fixed, the compartment looks clean, and you're just restarting a pilot that went out. Follow the unit's printed instructions exactly, and if it doesn't light cleanly after a couple of careful tries, stop.
Call a professional: any water near gas controls, any gas smell, a pilot that won't stay lit, a burner that looks or sounds wrong, or any doubt at all. Gas systems reward humility — and the service call is always the gentler lesson.
Your maintenance takeaway
A dead pilot after a leak is your heater asking for a proper diagnosis, not just a relight. Fix the water first, check the simple things safely, and hand the gas side to a professional at the first sign of real damage. That's the habit that keeps a leak from becoming something worse — call (833) 713-2101.