How to relight a furnace pilot light safely

To relight a furnace pilot light safely in Pocatello ID, turn the gas valve to Off, wait five minutes for residual gas to clear, set the thermostat below room temperature, then hold a long lighter to the pilot orifice while pressing the reset button for 30 to 60 seconds. If the flame holds after you release the button, turn the gas valve to On and raise the thermostat. If it goes out again, stop and call a technician - a pilot that won't stay lit usually means a bad thermocouple, a dirty orifice, or a draft problem, not bad luck.

We're Pocatello Furnace Repair Pros, and we've relit hundreds of standing-pilot furnaces in Pocatello Heights, the University area, and the older homes off Yellowstone Avenue. This guide walks you through the safe sequence, the reasons pilots fail, and the point where DIY stops being worth the risk.

How to relight a furnace pilot light in Pocatello ID: the safe sequence

Relighting a furnace pilot light in Pocatello ID is a ten-minute job when the furnace is healthy and a warning sign when it isn't. Before you touch anything, know what you're dealing with: a pilot light is a small standing flame that ignites the main burner on older gas furnaces, and it only works when gas, air, and a live thermocouple all line up.

Here's the sequence we use on service calls. Work in this order and don't skip steps.

1. Shut the gas off. Turn the furnace's gas valve (usually a red or black knob on the gas line) to the Off position. Wait a full five minutes. This clears any gas that pooled while the pilot was out.
2. Set the thermostat low. Drop it to 55°F or below so the furnace doesn't try to fire the main burner while you're working.
3. Find the pilot assembly. On most standing-pilot furnaces it's a small metal bracket near the burners with two tubes - one for gas, one for the thermocouple - and a reset button or a spring-loaded knob labeled Pilot.
4. Light it. Hold a long-barrel lighter or a fireplace match to the pilot orifice. Press and hold the reset button. Keep the flame on the orifice for 30 to 60 seconds.
5. Release and watch. Let go of the button. If the flame stays lit, turn the gas valve to On and set the thermostat back to your normal setting. If it dies within a few seconds, the thermocouple isn't sensing heat - that's a repair, not a relight.

If you'd rather not crawl around a cold furnace in a Pocatello January, we handle furnace pilot light repair Pocatello ID as a same-visit job - most thermocouple and orifice fixes take under an hour.

Why does my furnace pilot light keep going out in Pocatello?

A furnace pilot light that keeps going out in Pocatello almost always traces back to one of five causes: a worn thermocouple, a clogged pilot orifice, a dirty flame sensor on newer ignition systems, a draft from a loose burner door, or low gas pressure at the meter. In our experience, the thermocouple is the culprit about 60% of the time.

The thermocouple is the usual suspect

The thermocouple is a small rod that sits in the pilot flame and generates about 20 to 30 millivolts of electricity. That tiny current tells the gas valve it's safe to stay open. When the thermocouple ages - usually after 5 to 8 years - it stops producing enough voltage and the valve snaps shut. The pilot lights, burns for a few seconds, then dies. That pattern is the classic sign.

Dirt, drafts, and Pocatello's dry air

Pocatello sits at about 4,460 feet, and our dry air and dusty spring winds push fine grit into pilot assemblies. A pilot orifice the width of a pin can clog in a single heating season. Loose burner compartment doors - common on furnaces that have been serviced a few times - let cold air wash across the pilot and blow it out. If your pilot dies on windy nights specifically, that's usually the door or a flue draft issue.

Gas pressure and cold snaps

During the hard freezes we get in January and February, natural gas pressure at the meter can dip slightly when the whole neighborhood is drawing hard. If your pilot only fails on the coldest nights of the year, that's worth mentioning to whoever services the furnace. We see it most in the older housing stock around furnace pilot light in Pocatello Heights, where 1950s and 1960s furnaces are still doing the work.

Is it safe to relight a furnace pilot light in Pocatello Idaho?

Yes, it's safe to relight a furnace pilot light in Pocatello Idaho if you follow three rules: you can smell no gas, you wait the full five minutes after shutting the valve, and you never use a match taped to a stick or a lighter you have to lean into the burner compartment to reach. If you smell gas at any point, leave the house and call from outside.

Natural gas is odorized with mercaptan so you can smell it at concentrations as low as 1 part per million. If you catch even a faint rotten-egg smell near the furnace, don't relight - ventilate and call us or Intermountain Gas. A pilot that's out but the valve is open is the dangerous scenario, and it's the reason the five-minute wait isn't optional.

Two more safety notes. First, keep your face and sleeves out of the burner compartment when you light - pilot flames can flash a few inches. Second, if your furnace has a sealed combustion chamber or a hot-surface igniter (HSI) instead of a standing pilot, there's nothing to relight. Those systems spark or glow on their own, and a no-heat call on one of those is a different repair entirely. We cover that under furnace ignition repair Pocatello ID.

Common mistakes to avoid when relighting a pilot light

The mistakes we see most often on pilot-light calls are the ones that either waste an afternoon or create a real hazard. Here's what to watch for.

• Skipping the five-minute wait. Gas pools in the burner compartment. Give it time to clear.
• Holding the reset button for 10 seconds and calling it good. The thermocouple needs 30 to 60 seconds in the flame to build enough voltage to hold the valve open.
• Cleaning the orifice with a wire or needle. You'll widen it and change the flame shape. Use compressed air only.
• Relighting a pilot that's been out for weeks. If the furnace sat cold through a long stretch, have it checked before you fire it - spiders love pilot tubes, and a blocked burner can produce carbon monoxide.
• Ignoring a yellow or orange pilot flame. A healthy pilot is a crisp blue cone. Yellow means incomplete combustion, and that's a call-us-now situation.

If you're not comfortable working around a live gas appliance, that's a reasonable position. Our team handles gas furnace repair Pocatello ID daily, and a pilot-light service visit is one of the simplest calls we run.

Furnace pilot troubleshooting Pocatello: what the flame is telling you

Furnace pilot troubleshooting Pocatello homeowners can do themselves comes down to reading the flame. The color, size, and behavior of the pilot tell you almost everything about what's wrong.

• Blue, steady, about 1 to 1.5 inches tall: healthy. Leave it alone.
• Yellow or orange: incomplete combustion. Could be a dirty orifice, wrong gas pressure, or a blocked flue. Call a pro.
• Lifting or flickering: too much gas or a draft. Check the burner door gasket.
• Small and weak: partially clogged orifice. Compressed air, not a wire.
• Lights, then dies in 5 to 10 seconds: thermocouple or flame sensor failure. This is the most common pilot-light repair we run.

If you've relit the pilot three times in a week and it keeps dying, stop relighting it. Repeated relights on a failing thermocouple can eventually damage the gas valve, and that turns a $150 to $250 thermocouple job in 2026 into a $400 to $700 valve replacement. We see this pattern most on furnaces that are 15 years or older, and it's one of the reasons we recommend an annual residential furnace repair Pocatello ID inspection before the first hard freeze.

When to call a professional

Call a professional if the pilot won't stay lit after two attempts, if you smell gas at any point, if the flame is yellow instead of blue, or if the furnace is more than 15 years old and this is its second or third pilot failure of the season. Those are the calls where a DIY relight is just delaying a repair you're going to need anyway.

Pocatello Furnace Repair Pros works on standing-pilot and electronic-ignition furnaces across Pocatello and the surrounding neighborhoods. We diagnose the pilot, test the thermocouple and gas valve, clean the orifice, and confirm the burner compartment is sealed before we leave. If the furnace needs a part, we carry the common thermocouples and pilot assemblies on the truck.

One more thing worth saying: if your furnace is a 1980s or early-1990s unit with a standing pilot, a pilot that keeps failing is often the first sign the heat exchanger is on its way out. We check for that on every pilot call, because carbon monoxide is not something to guess about.

Frequently Asked Questions

How do I relight my furnace pilot light in Pocatello ID?

Turn the gas valve Off, wait five minutes, set the thermostat below 55°F, then hold a long lighter to the pilot orifice while pressing the reset button for 30 to 60 seconds. Release the button - if the flame holds, turn the gas valve On and reset the thermostat. If it dies, call a technician.

Why does my furnace pilot light keep going out in Pocatello?

The most common cause is a worn thermocouple that's 5 to 8 years old and no longer produces enough voltage to hold the gas valve open. Other causes include a clogged pilot orifice, a loose burner door letting in cold air, or low gas pressure during hard freezes.

Is it safe to relight furnace pilot light in Pocatello Idaho?

Yes, if you smell no gas, wait the full five minutes after shutting the valve, and use a long lighter rather than leaning into the burner compartment. If you smell gas at any point, leave the house and call from outside - don't relight.

Should I call a furnace repair in Pocatello for pilot light?

Call us if the pilot won't stay lit after two attempts, if the flame is yellow instead of blue, if you smell gas, or if the furnace is 15 years or older and this is its second or third pilot failure this season. A thermocouple replacement runs $150 to $250 in 2026.

How much does it cost to fix a furnace pilot light in Pocatello?

Most pilot-light repairs in Pocatello run $150 to $350 in 2026, depending on whether it's a thermocouple, orifice cleaning, or a gas valve issue. A full gas valve replacement typically lands between $400 and $700. We quote the price before we start work.

Get help with Furnace Repair in Pocatello

If your pilot won't stay lit or you'd rather have a pro handle it, our team is ready. We handle Furnace Repair Pocatello ID across the city, and a pilot-light call is usually a same-day fix.

Call (208) 764-8111 and we'll get your heat back on.