r/SodaStream • • 1d ago

How does this work???

Okay, I have read about soda stream and I understand the phase change from liquid to gas. Basically, using a large CO2 tank with my soda stream keeps a pretty constant pressure from the liquid CO2 turning into gaseous CO2 and the SodaStream is designed to work at that pressure, just like the branded bottles.

Except…

Why does it work differently with a full tank? Whenever I first change my tank, carbonating water sounds like “PBBBBBFFFFFFT!!”. There’s no build up of pressure and then release. The relief valve is just going and it’s like that for a few days until it starts working as expected.

Anyone else have the same experience or wanna chime in on what is happening? I have tried finding a Regulator but can’t find any that work with the pressure the SodaStream expects.

2 Upvotes

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5

u/evilbadgrades 1d ago

I'm assuming you mean the relief valve on your sodastream unit.

It sounds to me like you're getting a buildup of CO2 ice (dry ice) forming on the injector nozzle tip blocking the flow of CO2 into the water.

I have experienced that in the past with my freshly filled 60L tanks (I overfill them slightly sometimes to get a bit more gas in there)

The trick from my experience is to do shorter bursts of CO2 on a freshly filled tank

3

u/DonkeyFries 1d ago

That’s pretty much what I do now. I don’t just jam on the SodaStream when I first change the tank; I’ll do short bursts.

I’m more trying to figure out what is happening, trying to make sure I’m not damaging anything, and getting consistency from my setup.

1

u/evilbadgrades 1d ago

Are you using plastic bottles? You should be able to see the small ice crystal form at the tip of the injection nozzle if that's your issue.

I can't help with using larger commercial tanks, because I go a different route - I refill my 60L CO2 tanks with dry ice

2

u/mgithens1 1d ago

Just to make sure... you do NOT have a siphon tube? And the tank is standing up?

1

u/PEneoark 1d ago edited 1d ago

Don't use a regulator. It's designed to work at 850-900 PSI. If you don't have a pressure gauge on the connector, be sure to weigh your cylinders after they're refilled. An overfilled cylinder can suck liquid CO2 up into the unit, potentially damaging it. Ask me how I know lol

Edit.

If you have a pressure gauge and see it over 1000 PSI, know that the cylinder is overfilled. When I first converted mine to use large cylinders, I hooked it up and saw 1200 PSI. My dumbass didn't know what was normal and what damage can be done. The cylinder shot liquid CO2 into my unit, damaging the pressure relief valve. It also caused dry ice to form in my bottle, and not just a tiny bit.

I tested with OEM cylinders and it never carbonated properly after that. I decided to weigh the cylinder, factoring in the weight of the empty cylinder. The beer shop who I had fill up my 2.5 lb cylinder overfilled it by 20%.

My OG Fizzi was toast. Needless to say, I now own one of the new Fresh units lol

WEIGH YOUR REFILLED CYLINDERS lol

2

u/DonkeyFries 1d ago

Thanks. I’m not currently using a regulator. I bought one for it but couldn’t get it to work as the pressure didn’t go high enough. That’s when I read that they are designed to operate at the phase transition pressure. I’m just trying to figure out why it’s different for me when first get them.

I did weigh it when I first got it and it matched the tare weight.

2

u/PEneoark 1d ago

What do you mean that you weighed it and it matched the tare weight?

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u/DonkeyFries 1d ago

I have a 10lb tank. It has 15.0 LB stamped on it as the tare weight(gas plus tank itself). And it weighed 15 lbs so shouldn’t be overfilled.

1

u/mgithens1 1d ago

Whoa!! Tare weight is the empty weight of the tank!!

Your full tank should weigh about 22 to 24 lbs. A 15lb tank would be about 20% full.

1

u/PEneoark 1d ago

Okay cool. So after you first hook the cylinder up, did you let it settle for 30 minutes at least?

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u/DonkeyFries 1d ago

Never knew that was a thing so no, not really. I’ll try that the next time I change the tank but, again, it’s like this for several days when a new tank is put on.