How to use a gas BBQ on the first cook
Updated: 23 October 2026
The carton on the patio is still a kit: a six-burner wagon, a side burner, and a pile of bolts. The first cook fails when gas pools under a closed lid or a joint weeps at the hose. This page shows how to use a gas BBQ that afternoon: outdoors, soapy water on the joints, the lid open to light, and the cylinder off before the knobs. Which wagon to buy is on the [6 burner gas BBQ comparison](/hub/grills-and-barbecues/6-burner-gas-bbq). If your manual disagrees, the manual wins. Notes dated 21 October 2026, no lab cook. A qualifying purchase can earn a commission at no extra cost to you.
The carton on the patio is still a kit: a six-burner wagon, a side burner, and a pile of bolts. The first cook fails when gas pools under a closed lid or a joint weeps at the hose.
The carton on the patio is still a kit: a six-burner wagon, a side burner, and a pile of bolts. The first cook fails when gas pools under a closed lid or a joint weeps at the hose. This page shows how to use a gas BBQ that afternoon: outdoors, soapy water on the joints, the lid open to light, and the cylinder off before the knobs. Which wagon to buy is on the 6 burner gas BBQ comparison. If your manual disagrees, the manual wins. Notes dated 21 October 2026, no lab cook. A qualifying purchase can earn a commission at no extra cost to you.
Our top picks
| Badge | Product | Ignition | Gas in the box | Assembly | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  CosmoGrill CosmoGrill Pro Deluxe 6+1 with cover | Piezo | Regulator and hose not included | Required. Two boxes | 9.0 | about £299.99 | View offer |
| Alternative |  CosmoGrill CosmoGrill Pro Deluxe 6+1 | Piezo | Regulator and hose not included | Required. Two boxes | 8.8 | about £289.99 | View offer |
| Best value |  CosmoGrill CosmoGrill Emberr 6+1 | Piezo. Cross-lighting claimed | Clip-on propane regulator and hose | Required | 8.0 | about £279.99 | View offer |
On this page
Build it before you think about food
Reviews put assembly at anything from about 30 minutes to about four hours, so clear the afternoon before you promise food. Two people should lift the hood. Stand the cart on level paving.
GOV.UK outdoor fire safety says not to light a gas barbecue in a garage, a tent, an awning, or a caravan, and to keep it clear of sheds and fences. Fit the drip tray and the heat tents the manual names before any burner is lit. Leave the food in the fridge. If the box looks short of a regulator, check the buying guide.
Connect and leak-test outside
Connect the hose outdoors with every burner knob off. Clip or screw the regulator to match the cylinder. Check that the joint is tight and that the hose has no cracks.
Leak-test with washing-up liquid and water, never with a match. Open the cylinder while the knobs stay shut, and brush soapy water on the regulator nut, both hose ends, and any joint the manual marks. Growing bubbles mean gas is leaving, so shut the valve and do not light. The Gas Safe Register says to use a registered engineer if you are unsure. A TOV review that describes a weeping joint means you do not use that grill.
Light with the lid open, then preheat with it shut
Light with the lid fully open. Unburnt gas can sit in the bowl, and a closed lid turns the next spark into a puff at face height. Weber’s lighting page is cylinder on, one burner to high, ignite, then the others, then the lid down to preheat. Your manual names the knob. If the piezo only clicks, turn that knob off. Weber says that if the burner does not light within about five seconds, you wait five minutes. That pause is Weber’s figure. If you smell gas, shut the cylinder first. Weber suggests a 15–20 minute burn-in. Appliances Direct describes 10–15 minutes, so do not average them. How many people the grate holds is on the crowd page.
Yellow flame, shutdown, and the cabinet
A healthy flame is mostly blue. Char-Broil’s UK note says a solid yellow flame is wrong, while yellow tips on a blue flame can be normal. A lazy all-yellow flame can be a tripped regulator or a leak. Disconnect, wait, and reconnect slowly, then look again. If it stays yellow, leak-test before you cook.
Shut the cylinder or the regulator first, then the burner knobs, so the hose empties. GOV.UK and the Gas Safe Register both use that order. If a flame will not die, Calor’s emergency number is 03457 444 999. Do not carry a cylinder that is still alight. The Pro Deluxe listing, the matching 93416 listing, and Emberr’s maker page all forbid a canister in the cabinet during use. If those notes conflict with Calor, the appliance instruction wins.
When to stop and call someone
Stop if a joint still grows bubbles, the hose is cracked, or you smell gas and cannot clear it. The Gas Safe Register says to use a registered engineer rather than guessing. A patio hose is not the same job as fixed gas pipework indoors. If a flame will not go out after the cylinder valve is shut, use 03457 444 999 and keep people back.
Common questions
How do I leak-test a gas BBQ without a flame?
Mix washing-up liquid with water and brush it on the joints outdoors. Every burner knob stays off. Open the cylinder and watch the film. Growing bubbles mean gas is escaping, so shut the valve and do not light the grill. The Gas Safe Register says to ask a registered engineer if you are unsure, or if the hose is cracked. A match is not a test tool.
What if the piezo only clicks?
Turn the knob off. A click with no flame can mean the bowl already holds gas, so do not spark again at once. Weber says that if a burner does not light within about five seconds, you wait five minutes. That pause is Weber’s instruction. If you smell gas, shut the cylinder and clear the patio before a second try with the lid still open.
Is a yellow flame a stop or a clean?
A solid yellow flame means you do not cook on it. Char-Broil treats solid yellow as wrong and describes a reset: disconnect, wait, reconnect slowly, then look again. A leak is the other cause, so test with soapy water first. Yellow tips on a blue flame can be normal. If the flame stays yellow and no bubbles grow, stop and get a competent person.
Do I turn the cylinder off first or the knobs first?
Turn the cylinder or the regulator off first, then the burner knobs. GOV.UK and the Gas Safe Register use that order so the hose empties. Knobs first leaves the hose charged until next time. If the flame stays lit after the valve is shut, call Calor on 03457 444 999. Do not carry the cylinder while a flame is still on it.
Can the gas bottle stay in the cupboard while I cook?
Not while the burners are lit. The Pro Deluxe notes, the matching 93416 listing, and Emberr’s maker page say not to put the canister in the cabinet during use. Calor allows a bottle under a barbecue only when you are not cooking, and wants it at the side while you cook. If the notes disagree, follow the appliance.
Related pages
Sources
Public UK sources used for this comparison. Listing prices, stars and review counts are the amazon.co.uk figures for these ASINs, from saved listings dated 19 October 2026.
- Liquid Gas UK Consumer Guidance Sheet 39 (August 2020) (retrieved 19 October 2026)
- HSE ACOP L56, Gas Safety (Installation and Use) Regulations (retrieved 19 October 2026)
- Gas Safety (Installation and Use) Regulations 1998 (retrieved 19 October 2026)
- GOV.UK: fire safety outdoors (retrieved 19 October 2026)
- Calor: gas bottles for BBQs (retrieved 19 October 2026)
- BS EN 498:2012 catalogue entry (retrieved 19 October 2026)
- Gas Safe Register: BBQ safety (retrieved 19 October 2026)
- Registered Gas Engineer: LPG hoses (retrieved 19 October 2026)