Connecting Cask Ale for sale



  • Cask Beer must always be examined for smell, taste and clarity before connection to the beer dispense equipment, preferably as soon as possible after the beer has had adequate time to fine out (become clear and fit for sale).
  • If a beer engine is to be used to raise beer, the peg must be removed to allow air to enter the cask as beer is pulled, but it must be replaced at the end of service till the next session or the beer will lose condition and probably become flat. If CO2  is to be used (cask breather or aspirator), the peg must be removed and replaced by a gas spigot which should be screwed firmly into the spile hole with its pressure release cap screwed down. Ensure that the gas non return valve is in position before connecting to the pipe.
  • Whichever system is employed, the method of connecting a beer pipe to a cask is identical. The beer pipe is transferred from the empty cask to the full one, care being taken to ensure that a hop strainer is in position and in good order.
  • If Gas pumps are in use make sure the gas supply is turned on to the pump,otherwise the beer engine will be difficult to pull.
  • If a cask breather is used, turn on the Co2 supply and open the cask tap slowly to prevent disturbance of sediment.
  • If not using a cask breather, remove the vent peg before operating the cask tap.





  1. Given that your website seems to be supportive of the cask breather (aka aspirator or demand valve), may I suggest you refrain from using the term “top (or blanket) pressure” in connection with this equipment? Use of the word “pressure” merely serves to perpetuate a misconception, aided and abetted by CAMRA, that CO2 is applied to the beer at higher-than-atmospheric pressure.
    It is a simple, self-regulating diaphragm that only allows CO2 to enter the cask on a volume by volume basis as beer is drawn off. Once equilibrium at atmospheric pressure is restored the gas is turned off. Conversely, any excess produced by the beer is vented off to atmosphere, thus serving as a soft spile.
    Not only, therefore, does the aspirator protect the beer from oxygen and undesirable bacteria, by maintaining a layer of virtually pure CO2 it also helps to maintain the condition of the beer.
    I recommend reading Patrick O’Neill’s excellent book “Cellarmanship” which deals specifically with these subjects in the chapters headed “Carbon Dioxide” and “Demand Valve”. The former is particularly enlightening and explodes some myths about beer and CO2. Check out Partial Pressure and Dalton’s and Henry’s Laws if you really want to be technical.

Do you have a better answer? Leave a reply or an opinion