If you smell gas, leave first
- Walk out right away. Do not turn on lights, use a switch, or run the garage door opener on the way.
- From outside, or from a neighbor's house, call your gas utility's emergency line or 911.
- Stay out until the utility or fire department says it is safe.
- After that, call us about the water heater.
What a thermocouple does, in plain words
On a gas tank water heater with a standing pilot, the thermocouple is a short metal probe that sits in the pilot flame. The flame heats it, and it makes a tiny electrical signal that holds the gas valve open. If the flame goes out, the probe cools, the signal stops and the valve shuts off the gas.
That is why a bad one has such a typical story: the pilot lights while you hold the button, then dies a few seconds after you let go. Many newer heaters use electronic ignition and have no standing pilot, so the part may not exist on yours. Check the label or the manual.
Pilot won't stay lit? It is not always the thermocouple
Worn thermocouple
The classic case. Probe tips wear and corrode over time, and the pilot drops out after you release the button.
Flame in the wrong place
A weak flame, or one that does not wrap the probe tip, cannot heat it enough to hold the valve open.
Dirty pilot assembly
Dust or soot in the pilot tube starves the flame. A steady blue flame looks healthy, while a yellow or flickering one calls for a service visit.
Draft or venting trouble
A downdraft can blow the pilot out. If it goes out only when a fan or the furnace starts, tell us. This is a safety matter, because combustion gases may not be leaving the house.
Failing gas control valve
If a new thermocouple does not help, the valve may not be holding open. That repair costs more and often moves the question toward replacement.
Part, repair or new tank: how to decide
| What you see | Likely direction | Why |
|---|---|---|
| Pilot lights, dies when released, tank otherwise dry and quiet | Thermocouple replacement | A textbook thermocouple symptom |
| Pilot goes out only with wind, a fan or the furnace | Venting and draft check first | A new part will not cure a draft |
| New thermocouple, same behavior | Gas control valve repair or replacement | It is the part left in the safety loop |
| Rust at the base, wet floor, rumbling, or a very old tank | Tank replacement conversation | A new part on a failing tank only delays the bigger bill |
| Soot, scorch marks or a burnt smell | Stop using it and call | These point to combustion problems |
Water around the tank can mean the tank itself has failed, not the pilot.
What drives the cost of a thermocouple job
We do not post dollar figures, because the number depends on your heater. These are the things that move the price, roughly in the order they matter. When you compare two quotes, ask each company to list the same things: the part, the visit, any other fixes and the tank's condition.
On insurance: sudden water damage from a failed tank is the usual covered event, while a worn part and routine maintenance usually are not. Check your own policy.
A daytime visit and a night or weekend visit are not priced the same way. We offer same-day appointments when available.
A basic thermocouple is a small part. Some heaters use a thermopile or a model-specific assembly that costs more.
A heater in a tight closet, a corroded connection or a pilot tube that needs cleaning adds time.
A dirty pilot, a draft problem or a leaking gas fitting changes the scope. We tell you before doing more.
If the tank is near the end of its life, a new part may not be worth buying, and replacement is the fairer comparison.
Allendale, MI: gas heat and permits
Census Bureau estimates for 2020 to 2024 count about 5,900 Allendale Township households heating with utility gas, against about 1,651 using electricity. Heating fuel does not tell us what your water heater burns, but it shows gas service is common here. Learn where your gas shutoff is before you ever need it.
Professional Code Inspections handles building, electrical, mechanical and plumbing permits and inspections for the township. Replacing a gas water heater or changing gas piping may involve a permit and an inspection, while a small part swap may not. Ask PCI which applies to your job before work starts, and we will tell you what we see on the call.
Source: Census Bureau ACS estimates for 2020 to 2024, and the township's planning and zoning page.
What to have ready when you call
We handle water heater repair and water heater replacement in Allendale, Hudsonville and Walker. A few details help us give a useful first answer.
- Brand, size and age from the label on the tank.
- Whether the pilot lights, and how long it stays lit after you release the button.
- Any gas smell, soot or water at the base of the tank.
- Whether you have already tried to relight it more than once.