What you need
- Dish soap and water, mixed roughly one part soap to two or three parts water (or a commercial leak-detection solution)
- A small paintbrush, sponge, or spray bottle
- A flashlight
- A rag to wipe off the solution afterward
- Calm conditions: wind can blow bubbles away before you see them
The test, step by step
- 1
Burners off, grill cool
Make sure every burner knob, side burner and rotisserie burner is off. Don't smoke, and keep any flame or spark source away. The grill should be cool.
- 2
Open the gas supply
For propane, open the tank valve slowly, about one full turn. For natural gas, open the shutoff valve to the grill. This pressurizes the line up to the burner valves.
- 3
Brush on the solution
Apply soapy water generously to every connection, working from the supply toward the grill: tank valve and regulator coupling, regulator body, both ends of the hose, the hose along its length, the connection to the manifold, and on natural gas, the shutoff valve and flex connector fittings.
- 4
Watch for bubbles
Look closely at each joint for 15 to 30 seconds. A leak shows as growing bubbles or a foam that keeps building. Tiny bubbles that pop and don't come back are usually just from applying the solution.
- 5
Close the gas and act
Turn off the supply. If you found no bubbles, wipe the connections clean and you're done. If you found a leak, see the table below before using the grill.
Where leaks show up and what to do
| Location | Common cause | What to do |
|---|---|---|
| Tank valve to regulator coupling | Coupling not fully tightened, worn or missing O-ring/seal | Close the valve, disconnect, check the seal, reconnect hand-tight, and retest. If it still bubbles, try a different tank. Persistent leaks mean the regulator or tank valve is bad. |
| Tank valve stem | Faulty tank valve | Close the valve, disconnect the tank, and move it away from the house. Take it to your propane supplier or exchange. Don't use it. |
| Regulator body or vent | Cracked housing or failed diaphragm | Replace the regulator and hose assembly. |
| Along the hose | Cracks, abrasion, rodent chewing, heat damage | Replace the hose. Never patch or tape a gas hose. |
| Hose to manifold fitting | Loose fitting or damaged flare | Tighten with the correct wrench, holding the back fitting so it doesn't twist. Retest. If it still leaks, have it repaired. |
| Natural gas shutoff or flex connector | Worn valve, damaged connector, poor joint | Call a qualified gas technician or plumber. Natural gas supply line work isn't a DIY job. |
| Bubbles near knobs or valves | Leaking burner valve | Don't use the grill. Valve leaks need a repair by someone who works on gas grills. |
What a soap test can't tell you
The test checks connections that are under pressure when the burner knobs are off. That covers the tank, regulator, hose and supply fittings up to the valves. It does not check:
- Leaks inside the burner valves when they're open, or the gas path inside the grill beyond the valves.
- Blocked burners or venturi tubes, which can send gas backward out of the air shutter and cause a fire behind the panel. That's a different problem. See spiders in burner tubes.
- Pipe leaks in a natural gas line buried underground or inside walls.
If you smell gas when the grill is running but the soap test is clean, or you smell gas near the knobs, stop using it and have it checked. Our gas smell repair page covers the likely causes.
When to do it
- Every time you connect a new or refilled propane tank
- At the start of grilling season, or a couple of times a year if you grill year-round
- After any repair that touched a gas fitting
- After a grill has been moved, knocked over, or tipped by wind
- After a long period unused, especially if rodents might have been in the cabinet
- After wildfire smoke, heat or ash exposure, before relighting
- Any time you notice a faint gas smell around the grill
Getting help
Replacing a propane hose and regulator is something many homeowners do themselves, using the part made for their grill. Work on a natural gas supply line, burner valves, or anything you're not sure about should be done by someone who works on gas appliances. Our techs carry common regulators and hoses and can test the full system during a grill inspection.
Common questions
How often should I soap-test my grill?
Every time you change the propane tank, and at least once or twice a year for a natural gas grill. Also any time something has disturbed the connections.
Can I use a gas leak detector instead?
Electronic detectors can help locate the general area of a leak, but a soap test pinpoints the exact connection. They work well together.
Should I use thread sealant or Teflon tape on the tank connection?
No. The tank coupling seals with an internal O-ring or seal, not threads. Tape or sealant there can actually prevent a proper seal.
The regulator coupling leaks only with one particular tank. What's wrong?
Likely the tank's valve or its internal seal. Swap the tank at your exchange or supplier.
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.
Buying advicePropane vs. Natural Gas Grills
How propane and natural gas grills differ in heat, convenience, setup and safety, and when converting a grill from one to the other makes sense.
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.
SafetySanta Ana Winds, Ash and Your Outdoor Kitchen
What to do with your grill and outdoor kitchen before, during and after Santa Ana winds and wildfire ash, including how to clean ash safely and check gas appliances.
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.
RepairGas Smell at the Grill
Smell gas at the grill? Safety steps first, then the common leak points and how a technician finds and fixes them.
RepairRegulator & Hose Replacement
Worn propane regulators, cracked hoses and tired natural gas flex connectors replaced and leak tested.
RepairGas Valve Replacement
Stiff, stuck or leaking burner control valves replaced and leak tested by a technician, not a weekend project.
RepairNatural Gas & Propane Problems
Supply-side problems on propane and natural gas grills: wrong orifices, undersized lines, regulators and bad conversions.
Found bubbles?
Shut the gas off and call or text us. We'll tell you what part is likely needed and get it fixed.