Erratic Bitter Fobbing


Hi all. I have recently become cellar man to a busy bar/night club and come across a problem with the Bass bitter which has stumped me and the tech guy. There are three pipe lines two fed from keg one, one from keg two. These lines go up to the coolers upstairs then back down to the two bars. Keg two is fine but one of the lines from keg one is erratically fobbing. Right the problem..

On the front side of the bar the Bass bitter pump which is used most frequently will not stop intermittently fobbing it will be calm during the day with less wastage but during high usage periods it can fob continually pouring nothing but creamy body even with or without the diffuser. Yet at times it can be perfectly fine pouring 100’s of pints before all of a sudden starts fobbing, lose around 10 pints then be perfectly fine again.

First idea was that it need a good clean so i have done even after weeks of cleaning the problem didn’t go away, next i serviced and cleaned all the cellar equipment which made on difference. So i finally gave in and called a tech who basically came (when it was behave) in checked the gas flow and mix, checked the connector, coolers and said everything was fine and it was due to dirty lines. After the 4th tech guy coming up with the same thing i’m at a loss.

I am now annoyed by there judgment as all other 32 are clean and problem free, i’ve even tried a different brand of line clean just to see if it will affect it but still no change. I am totally out of ideas, am I missing something?

Mr RAnts


  1. This is a good one providing the lines are clean…. you don’t say how long the lines are to each tap? For example does this happen after you have changed a barrel? Is the fob detector working? Is it happening when you have changed a gas bottle? Is it when you are very busy?

    There doesn’t seems to be anything that stands out could possibly be an intermittent fault on the secondary gas valve. Then the one tap might seem Ok if you have a long run. How long has it been happening? Did it start when something was changed? The problem you have, it is not happening when the technician is there. So it is like trying to find a needle in a haystack.

    Try to observe all these things when it happens so you can tell your local tech. Something like this would be very difficult to diagnose from a distance.

  2. I’m glad to see such a quick and detailed reply and will try my best to clear up the pervious points.. 1. The distance from keg to tap is quite a distance with most of the lines hidden in walls and floors. It’s a large building where the lines lead from the cellar through a wall space into the roof then down into the dry store where there is a nine glycol coolers. From there they go back into the roof space then travel down two floors in a column down to the bar where they run under the bar floor then up to the pumps. Each pipeline holds about seven pints of product.

    2. It really can happen at any time without warning no matter how long the keg had been connected it could be just after, in the middle or just at the end of a keg and anywhere in between. All seals seem to be fine on the connector one tech guy even striped it down gave it a good clean and re-assembled it. The fob detector appears to be working fine. Gas pressure does not appear to be affecting it. Finally it can happen at anytime during trade be it a quite sunday day or a packed out saturday night.

    3. It just started out of the blue but the bar has had a recent re-fit including a new bar surround and pumps but it was a few months after that the problems started. I don’t understand how a system which was ok five years pervious can suddenly become very unreliable with no clues to the cause. I blame something that’s happened when the new bar surround was built yet tech’s say it wouldn’t affect it.

    .. I have had different tech guys come out to look at it who just want to claim its dirty lines but i feel this is more of an excuse, than a genuine problem as in my last post i’ve detailed how i’ve tired to eliminate that cause totally. I am satisfied the line is in good condition.

    This is now becoming a large stock issue as busy staff are pouring away potentially five pints every time it starts fobbing until it starts running fine again. This can happen on average four times a day which is a potential loss of 140 pints a week down the drain. That’s before you start to take in account staff drinks, genuine wastage and line clean allowances. Its a stock nightmare which is frustrating my boss who is passing the buck onto me because the tech guys are telling him its my dirty lines.

    It is a tiny needle in a truly massive haystack which is giving me a humongous headache. 🙂

    Mr RAnts

  3. Thank you for the detailed reply it sounds like a pressure drop in the line, that would result in gas leaving the liquid which could be the cause of your fobbing. And as you have said there are seven pints in your lines that could result in your ten pint loss before it corrects itself.

    So I would start to look for the cause of this pressure drop. This could be an intermittent fault with the secondary valve and the only way you could check this would be for the engineer to change it, or if you have an electric pump that might fail to cut in now and again, the cause can be so many things. That is why you have go with the technician on the job.

    However as I have said before it very difficult to diagnose this remotely and I am probably completely and totally wrong, it is very easy to comment on something when you are only looking for certain things. Perhaps there are others who are reading this who have a completely different view.

  4. It would be a simple matter to put all lines on single kegs.I know it is another keg on usage,but it might elliminate your problem.It would be quite easy I imagine for your Tech to do this,and it would perhaps stop your pressure drop,if that is the case.That amount of wastage is not acceptaable and your service provider should sort it out as a matter of urgency. I would suggest ringing the local Tech Services manager and ratchet up the importance of your problem.

  5. As admin says hard to diagnose especially without seeing the system, could be faulty pump (gas or electric) or secondary, also have you checked product temperature when it is fobbing? and does the other line connected to the keg fob at the same time?

  6. Does the line run over any flash coolers that may be heating up when you are serving other products had it before took me weeks to work out what was wrong

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