# Marzocco GB5 Dosing issue



## woliwols (Mar 20, 2014)

hello all,

Not sure if this is in the right place but here goes.

We have a GB5 at work and i love it, great machine however recently, the third group is wierd. It is pouring the at twice the speed as ther two groups when you no / an empty portafilter in the group. nottoo of an issue as shots still to pour the correct time but obviously im concerned about the extra pressure the coffeeunder compared to the other two groups.

also the hot water tap now a growning noise and stas off fast but then slows d i dont know if this is related and i havent had time to investigate this yet.

any help is much appreciated

Oli


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## espressotechno (Apr 11, 2011)

Depending on the age of your GB5 and when it was last serviced, it may just need a descale of the haet exchangers, flowmeters & group heads.

But.....For a 3 group commercial machine like the GB5, you should really call on the services of the local Marzocco engineer, or a good local independent espresso engineer.


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## Bean & Leaf (Jul 11, 2014)

the lamarzocco range do not have heat exchangers. if the third group is dosing more especially without coffee restriction in the portafilter, it means the restrictor is non esistent in the flowmeter. as the dispense valves areon the group head, the earlier models had a restrictor on them too.

contact http://www.bean-leaf.co.uk they will come out to you and repair


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