Flow issues with magic box - nothing seems to work

[Sarudore]

Hey brewers, long time reader first time poster.

Background:
- I bought myself a new magic box that I'm using to pump out kegs sitting in ice buckets at parties to keep it cold.

Specifics:
- Tubes are 6mm ID
- metal coils are probably only 3mm ID
- I've got one very large gas bottle with a splitter to two kegs at a time. (using one reg to run two kegs at a time)
- Each keg beer out line leads to one of the taps of the magic box.
- brand new regulator and beer lines

Issue:
- I can't get the flow fast enough and it's painfully slow pouring a beer.

Attempted so far:
- increasing reg pressure (flow rate didn't change but beer became heady with more pressure)
- fill esky completely with ice (no effect, beer is very cold)
- checked for gas leaks (none that I can hear anywhere along the lines)
- tried multiple kegs including beers and a cider(no change)


Are the coils too thin? What else could be the issue. Let me know if any further questions or if more pictures are needed.

 

[Online Brewing Supplies]

Remove a tap and push some water through, it will tell you which part is not allowing flow.
Coils unless obstructed should be more than enough to get good flow.
Nev

 

[pcmfisher]

There would be a fair bit of resistance from that length of 3mm id coils.
I don't really know how fast they are supposed to pour, but I wouldn't imagine it would be too fast as it then wouldn't cool properly.

 

[itmechanic]

I doubt the coils are 3mm ID, most are 5mm at least. A coil is normally 10-16 meters or so long and a fair bit of pressure is needed to push beer through, try 30psi and see what happens. of course at this pressure and with cold kegs you will eventually over carbonate if using co2, hence the need for a mixed co2/nitrogen blend. You may have even frozen some water in the coil which is restricting flow.

 

[Sarudore]

Thanks for your responses.

I've got one of those small pressurised bottles used for keg cleaning that used to push water through it so i'll try remove the tap and see if that makes a difference.

Coils on closer inspection are probably 4-5mm ID. They are 10m coils. I'll try 30PSI and see how it goes as well.

 

[HBHB]

Try contacting the retailer and grab the spec's. Surely they will know what their own product is and how it works best. If it's from Ebay, good luck.

They're a pretty simple system, gas in, beer out anything that blocks passage of either is a bad thing. 10m of 4mm is going to create a lot of resistance for the beer to be pushed through. Most of those coils coming into the country are 6mmx8mmx10m.

Pouring at 30psi is going to end up with a seriously over carbonated beer at some stage if used for lengthy periods (not as badly as it would if the beer keg was cold)

 

[MHB]

I wish you guys would post in kPa, I was in primary school when Australia made the change and a bloody good idea it was to!
Over Carbonation isn't an issue if the beer is warm enough, have a look at the gas temperature solubility tables on Braukaiser.
30psi is roughly 200kPa, at 200kPa and 20oC your CO2 saturation is only about 5g/L about right for an Aussie Ale or European lager (well in the range).
It probably isn't going to work as well with cheap taps and coils but with Miracle Plates and well made commercial taps the target flow rate is about 1L in 10 seconds that gives the right flow dynamics in the system to have a good pour and keep the right carbonation you are generally in the range of 180-250kPa.Fill up a keg with water and measure the flow, get someone to help you and time the flow, try to get close to the 1L/m.
Couple of things to look at: -
Have a look at the end of the coil, just see if there are any burs or its been pinched off a bit during manufacture, if it has/is clean out the opening. Blow through make sure there are no obstructions or kinks/pinches in your lines.
Cooling is not about flow through but residence time, for best results the coil or plate should hold a bit more than a serve (schooner), if you take a short pause between pours, the beer will get a lot colder pretty fast. its beer sitting in the ice water that gets cool doesn't really work well if there is a constant flow.
Ice and water cool a lot better than does Ice alone, if you have Ice against the coil, the heat has to transfer by conduction and Ice is a really crappy conductor, water being a fluid can when it warms up rise to where the ice is floating get cooled down and recirculate - it works much better.
Always add beer first then Ice and water, Ice is often colder than 0oC if there is any water in the coil/plate you can freeze it solid and it takes a devil of a long time to thaw when its in ice, so Always run the beer through the coil before adding the ice to the box Always...

Mark

 

[mr_wibble]

My kegging system did this the other day on the soda water tap - The pipe was against the side of the chest freezer element, and although set to 3.3C, water had frozen in the line.

Could there some water freezing in the line?

EDIT: Ah, MHB covered that already above.

-kt

 

[woodwormm]

The pipe was against the side of the chest freezer element, and although set to 3.3C, water had frozen in the line.

hehe sounds familiar, on more than 1 occasion i've had to pour a boiling kettle over a beer line to thaw it out.

to OP, my money's on something frozen in the line blocking it.