Nearly every home relies on a hot water heater, but keeping the pilot light lit can often prove troublesome. If this sounds familiar, don’t despair – the cause is usually simple to identify and remedy. This guide provides an overview of common issues that can cause a pilot light to keep going out, along with DIY troubleshooting tips to resuscitate your water heater.
Common Causes of a Pilot Light Going Out
A pilot light that keeps going out can be frustrating. But don’t worry – this issue can often be fixed with some troubleshooting and minor repairs. Here are some of the most common reasons your water heater’s pilot light may repeatedly go out:
1. Dirty or Clogged Pilot Tube
The pilot tube brings gas from the supply line to the pilot light assembly. Over time, debris and dirt can build up inside this tube, blocking the flow of gas. If the gas can’t get through properly, the pilot light will not stay lit.
To clean the pilot tube:
- Turn off the gas supply and allow the area to ventilate. Safety first!
- Remove the pilot tube from the pilot light assembly.
- Use a pipe cleaner or compressed air to loosen and blow out any dirt or debris inside the tube.
- Reattach the cleaned pilot tube and make sure all connections are tight.
2. Faulty Thermocouple
The thermocouple is a heat-sensitive device that sits right in the pilot light flame. Its job is to detect when the pilot light is lit and send a signal to the gas control valve to remain open, keeping the pilot light on.
If the thermocouple is faulty, it may fail to hold the valve open. As a result, the pilot light can go out repeatedly. Signs of a bad thermocouple include:
- The pilot light won’t stay lit after being relit multiple times
- The thermocouple isn’t producing the proper electric voltage
To replace the thermocouple:
- Turn off the gas supply and disconnect the thermocouple from the gas valve.
- Unscrew the faulty thermocouple and remove it.
- Install a new thermocouple of the same model and reconnect to the valve.
3. Improper Gas Supply
For the pilot light to stay on, it needs proper gas flow and adequate gas pressure. If the gas line is damaged, obstructed, or the pressure is off, the pilot may go out.
To check the gas supply:
- With the pilot lit, a multimeter is used to test the gas pressure at the gas control valve.
- Compare to the manufacturer’s recommended pressure range.
- If it is too low, check for leaks/blockages in the gas line. A plumber can adjust the line pressure.
4. Loose or Faulty Electrical Connections
The thermocouple, gas valve, and igniter all rely on secure electrical connections to function properly. Loose wiring or faulty electrical components can prevent the pilot from staying lit.
To check connections:
- Make sure all wiring to the gas valve and thermocouple is tight and corrosion-free.
- Verify electrical continuity in the circuits with a multimeter.
- Replace any damaged or deteriorated wires or connections.
5. Other Possible Causes
Less common causes for a pilot light that keeps going out include:
- A faulty pilot light assembly (weak flame, clogged ports)
- A malfunctioning water heater temperature and pressure relief valve
Hopefully, this gives you a good overview of the most likely reasons your water heater’s pilot light won’t stay lit. With some troubleshooting and minor repairs, you should be able to get the pilot back in working order.
Troubleshooting and Repair Steps
Do you have a temperamental pilot light that won’t stay lit? Don’t call the repairman just yet. There are several DIY troubleshooting steps you can take to get your water heater’s pilot light working again.
1. Turn Off the Gas Supply
Before doing any work on your water heater, it’s crucial to turn off the gas supply. Safety first! A gas leak could lead to a fire hazard or explosion.
To turn off the gas:
- Locate the gas shut-off valve on the gas line leading to the water heater.
- Use a crescent wrench to turn the valve clockwise to the “Off” position.
- Confirm the gas is off by trying to relight the water heater – it should not ignite.
2. Check the Pilot Light Assembly
The pilot light assembly includes the pilot hood, flame nozzle, and igniter/electrode. If any of these components are dirty, clogged, or damaged, it can prevent the pilot flame from lighting properly.
To inspect the assembly:
- Remove the pilot hood to access the nozzle and igniter.
- Clean any dirt/debris with compressed air or a pipe cleaner.
- Replace the igniter or hood if it is cracked or worn.
3. Check the Thermocouple
As explained earlier, the thermocouple tells the gas valve when the pilot is lit. To test if the thermocouple is faulty:
- Light the pilot and let it run for 90 seconds. Does it stay lit?
- With a multimeter, check that the thermocouple is producing the minimum voltage, usually 20-30 mV.
- If not, the thermocouple likely needs to be replaced.
4. Check the Gas Supply
Even if the thermocouple checks out, an issue with the gas line or valve can prevent the pilot from lighting.
To inspect the gas supply:
- With the pilot lit, check the gas pressure at the valve with a manometer.
- Pressure must be within the appliance’s specified range, often 5-14 inches of water column.
- If pressure is too low, check the gas line for leaks and blockages.
- The gas valve may need to be adjusted by a professional if pressure can’t be corrected.
5. Check Electrical Connections
Loose wire connections to the gas valve can stop the pilot from lighting.
- Remove and inspect wires connected to the gas valve, thermocouple, and igniter.
- Check for corrosion and secure any loose connections.
- Verify the electrical continuity of each circuit.
- Replace damaged wires.
Following these troubleshooting steps should help identify any issues preventing your pilot light from remaining lit.
Also Read: Water Heater Installation Basics: A Step-By-Step Guide
Preventative Maintenance
Taking some simple maintenance steps can go a long way towards keeping your water heater’s pilot light running smoothly for years to come. An ounce of prevention is worth a pound of cure, after all! Let’s look at some maintenance tips to help avoid annoying pilot outages.
Regular Cleaning and Inspection
Over time, small bits of dirt and dust in the air can clog up the pilot light assembly. A regular cleaning helps remove this debris:
- Every six months, inspect the pilot hood, nozzle, electrode, and thermocouple.
- Use compressed air or a pipe cleaner to loosen and remove any dirt or buildup.
- Wipe down components with a clean cloth.
- Make sure connections are snug but not overtightened.
You should also check for any early signs of damage or wear to the assembly pieces. Are the electrode and nozzle in good shape? Is the thermocouple wire intact? Better to replace parts at the first sign of trouble.
Regular Replacement of Parts
Some pilot light components have a limited lifespan and need replacement every few years:
- Thermocouples tend to wear out after 2-3 years of use. Replace yours as a precaution if it’s over three years old.
- The pilot assembly may need replacement after 5+ years to ensure optimal performance.
To replace these parts:
- Shut off the water and gas supply before starting.
- Remove the old part and disconnect the wiring.
- Install new components and reconnect wiring.
- Double check all fittings are tight, then restart the water heater.
With regular maintenance to nip any problems in the bud, your pilot light can keep going strong for years of reliable service. A few minutes of preventative care will save you the time and hassle of repeated pilot light callouts down the road.
Conclusion
Dealing with a pilot light that won’t stay lit can be a pain. But don’t worry – in most cases, it’s an easy fix. Let’s do a quick recap of the key points we covered:
- Dirty pilot tubes, faulty thermocouples, gas supply issues, and loose electrical connections are common culprits for a pilot that keeps going out.
- Troubleshooting steps like checking the thermocouple voltage, gas pressure, and electrical connections can reveal the cause.
- Replacing parts like the thermocouple or cleaning the pilot assembly often solves the problem.
- Preventative maintenance, like regular cleanings and replacing worn parts, helps avoid future pilot light problems.
With a bit of DIY troubleshooting and maintenance, your water heater’s pilot light will be there when you need it. No more chilly showers or baths!