DIY CO2 Kit – High Pressure Canister Common Issues

Every CO2 system will have its own issues and advantages. The high pressure canisterDIY CO2 Kit has its own issues as well and here are some tips to overcome the problems.

Difficult Screwing Back Regulator

This is the number one issues readers asked me about.

The problem is that immediately after pouring the water into the canister, most people experienced a hard time screwing back the regulator. The thread just won’t sit well.

The problem is caused when the pressure is building up and pushing the regulator upwards. The problem is further compiled by the fact that the screw threads are very precisely machined, and the slightest slant will cause make it difficult to screw it into position.


The screw threads are very fragile. Any excessive force will cause the thread to burr. Once the thread is burred it will be even more difficult to screw back.


For every reaction and then I will use some Vaseline Petroleum Jelly to the screw threads, and the mouth of the bottle. Make it part of your routine.

  1. Release remaining CO2 in canister via the bubble counter.
  2. Unscrew the regulator slowly until you hear hissing sound.
  3. Let the pressure deplete before unscrewing the regulator fully.
  4. Once the pressure has been released fully unscrew the regulator and place it aside.
  5. Do not pour away the solution for now as we do not want to get the screw thread wet.
  6. Apply petroleum jelly on the screw thread and the opening. Apply on the threads on the regulator as well.
  7. Screw back the regulator so the petroleum jelly will be spread evenly along the threads.
  8. Repeat a few times and you will find that now the screwing motion is extremely smooth.
  9. Proceed with you usual steps.
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A word of caution when unscrewing and screwing the regulator. Do not apply too much pressure on the bubble counter neck. This screw thread here is only a few rounds of thread and can deform or even break after a while.

caution when screwing back the regulator
The bubble counter neck is fragile

Once broken the entire kit is unusable. So far, they do not sell the regulator separately.

CO2 Don’t Last Beyond 2 weeks

If your CO2 does not last at least 2 weeks then you have a leak somewhere.

Most leaks develop around the neck between regulator and the canister. There is a rubber O ring at the end of the thread of the regulator. You need to screw the regulator all the way until it compress the O ring. But not too tight.

I realised if you screw too tightly the O ring will be deformed and leak will take place.

Another place most likely to leak will be the built-in bubble counter. Check if you have tighten the bubble counter.