Thursday 6 May 2021

Checking & Testing CO2 Gas Lines for Leaks (How To Guide)

One of the greatest fears of many home brewers utilising CO2 tanks and kegs for carbonating and dispensing their beer, is that of a leak in their gas lines. Even the tiniest of leaks can empty a full CO2 bottle overnight which is an unnecessary inconvenience, and expense.

A great tool you can use to track down a CO2 leak is a trigger spray bottle filled with water and a couple of squirts of dish washing liquid. Spraying this solution onto hoses/connections etc will cause bubbles to show/form/pop wherever there's a gas leak.

Here are a process you can use to isolate and track down any leaks you may have in your CO2 gas lines.

  1. Isolate where the problem is - as a first step I disconnect my gas line from any keg(s) it may be connected to. Open the gas on your bottle and adjust your CO2 regulator pressure to 10psi

  2. Close the gas from your bottle and leave overnight. Check the regulator pressure gauge values to ensure they haven't dropped to 0 after this time. Some reduction in pressure may occur, due to changes in atmospheric temperature etc - a slight reduction over a long time doesn't necessarily indicate a leak, however, the pressure being reduced to 0 over any time period does.

  3. If the pressure has dropped to 0 you have a leak - and because you've disconnected the gas line from your kegs, we've narrowed it down to one of the below places

    The connection between gas bottle and gas regulator
    The regulator housing (including gauge connections)
    The regulator output/connection to your gas lines
    The disconnect on the end of your gas line(s)

  4. Use your dish washing liquid spray solution mentioned previously to cover the above areas and watch for bubbles forming/moving. Bubbles will automatically form when you spray which is fine - what you need to watch for is bubbles forming, moving and popping which indicates the presence of pressure/gas

    An example of bubbles after a gas disconnect being sprayed. Bubbles are OK - moving/popping bubbles are not

  5. Next step would be to pressurise your keg(s) and spray the openings and posts to see if any bubbles form

  6. Most leaks are easily fixed by tightening the fittings/connections. It's knowing which connections need to be tightened that is the problem.
Have you had problems with gas leaks in your setup? Let me know in the comments below

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  1. Every step you have is correct. When that fails.... After going through four 5lb bottles I dunked my still new 3 valve pressure regulator under water and discovered a slow leak from the gauge. The company warrantied me a replacement.

    1. Sorry to hear of your battle with leaks, and thank you for the feedback. Glad you got it sorted and you were able to get a replacement regulator!