Where they hide and why
Each burner on a gas grill has a tube at the front, called the venturi, that slips over the gas valve's orifice. Gas shoots out of the orifice into the tube, and as it does, it pulls air in through an opening called the air shutter. The gas and air mix in the tube and travel to the burner ports, where they burn.
That tube is a dark, protected, slightly warm tunnel. Spiders build webs and egg sacs in it, and some insects (mud daubers and other wasps, in particular) build nests there. Grill makers and the U.S. Consumer Product Safety Commission have both warned about it. A common explanation is that some spiders are drawn to the odorant added to gas, though the dark tunnel is attractive on its own.
In Los Angeles, spiders stay active year-round thanks to the mild climate, so it isn't only a spring problem. Any grill that sits for a few weeks is at risk.
Warning signs of a blocked burner tube
- One burner with lazy, yellow or orange flames while the others are blue
- A burner that lights only partway along its length
- Weak heat from one section of the grill
- Popping or a flame that lifts off the ports
- Flames or heat coming from around the control knobs
- Scorched or melted knobs, or discoloration on the control panel
- A burner that won't light at all even though others do
- A gas smell near the knobs while the grill is on
How to clear a burner tube
You'll need a screwdriver or nut driver for your grill, a venturi brush (a long, flexible bottle-style brush), a straightened paper clip, a flashlight, and gloves.
- 1
Shut off the gas and let it cool
Close the tank valve or natural gas shutoff. Make sure the grill is cold.
- 2
Remove the grates and heat plates
Lift them out so you can reach the burners. Take a photo of how the burners sit before you remove anything.
- 3
Take out the burner
Most burners are held at the back by a screw, cotter pin or clip. Remove it, lift the back of the burner, and slide it backward off the valve orifice. Note whether the igniter or a crossover tube needs to be moved first.
- 4
Clean the tube
Look through the venturi with a flashlight. Run the venturi brush all the way through several times. For a stubborn nest, flush with water from a hose through the tube and shake it out, then dry it completely before reinstalling.
- 5
Clear the ports
Use the paper clip to gently clear any blocked ports along the burner. Don't widen them. Brush the burner exterior.
- 6
Reinstall and test
Slide the venturi back over the orifice. This is important: make sure the tube is fully seated on the valve, not resting beside it. Secure the back of the burner, reinstall plates and grates, turn on the gas, and light each burner. Flames should be blue and even.
Prevention
- Use the grill. Regular heat keeps spiders out. A grill used weekly rarely has a problem.
- Clean the tubes during deep cleans. Whenever the burners come out, run a venturi brush through. Our deep cleaning guide covers it.
- Check after any break. If the grill has sat for more than a few weeks, inspect the burners before the first cook. See off-season grill care.
- Spider guards or screens. Some grills come with mesh screens over the air shutter openings, and aftermarket ones exist for some models. Make sure any screen is designed for your grill and doesn't restrict airflow.
- Watch your flames. Yellow, uneven or partial flames on one burner are the first sign. Catch it early.
Not just grills
The same problem affects anything with a burner and a venturi: gas fire pits, patio heaters, side burners, outdoor gas fireplaces, and pizza ovens. Patio heaters are notorious because they often sit unused for months. If a fire pit or heater lights poorly or won't stay lit after a break, spiders are a likely suspect.
Common questions
How often should I clean the burner tubes?
At least once a year, and before using the grill after any break longer than a few weeks. More often if you see uneven or yellow flames.
Can I just blow compressed air through the tube?
It can clear loose webs, but egg sacs and nests usually need a brush. Never blow air into the valve or orifice.
My knobs melted. Is the grill safe?
Not until it's checked. A flashback hot enough to melt knobs may have damaged the valves, wiring or manifold. Have the gas components inspected before using it.
Will spider spray keep them away?
We don't recommend spraying insecticides in burner tubes or near cooking surfaces. Regular use and cleaning work better.
Related guides and repairs
Grill Safety Checklist
A practical safety checklist for gas grills and outdoor kitchens, from placement and gas checks to grease fires and what to do in an emergency.
Care & how-toBasic Cleaning vs. Deep Cleaning
The difference between a routine grill cleaning and a full teardown, with step-by-step instructions for both.
Care & how-toOff-Season Grill Care in Los Angeles
How to look after a grill through LA's slower months, in regular use or sitting idle, including rain, marine layer, pests and Santa Ana season.
Care & how-toGetting Your Grill Ready for Summer
A practical pre-summer checklist for gas grills and outdoor kitchens: what to inspect, clean and test before the season's first big cookout.
TroubleshootingMice and Rats in Your Grill
Signs of mice and rats in a grill or outdoor kitchen, how to clean up safely, what they damage, and practical ways to keep them out for good.
RepairSpider & Insect Blockages
Spider webs and insect nests in burner venturis cleared before they cause weak flame or a flashback fire.
RepairLow Flame & Weak Heat
Flames stuck on low and a grill that won't get hot: regulator bypass, blockages and gas supply problems diagnosed and fixed.
RepairUneven Heat & Hot Spots
One side burning, the other barely warm: clogged ports, damaged burners and warped heat plates found and fixed.
RepairBurner Replacement
Rusted, cracked or split burners replaced with matched parts, set on their orifices and tested for clean, even flame.
Flames looking off?
Call or text, or send a short video of the burners lit. We can usually tell what's going on.