How to Perform a Closed Transfer from Fermenter to Keg: A Step-by-Step Guide for Homebrewers

Introduction to Closed Transfer in Homebrewing

Closed transfer is a crucial technique in homebrewing that ensures your beer remains free from contamination and oxidation. This guide will walk you through the process of transferring your brew from the fermenter to the keg while maintaining its quality.

Benefits of Closed Transfer for Homebrewers

Closed transfer offers several benefits, including reducing the risk of oxidation, maintaining the beer's freshness, and improving the overall taste. By using this method, homebrewers can achieve a professional-quality brew that will stay fresher for longer.

Closed transfers using pressure also have the benefit of maintaining any carbonation within the beer, so if you've cold crashed in your pressure fermenter, you've already gotten a head start on carbonating and don't want to lose some of it by having to de-pressurise your fermenter to get the beer out.

Essential Equipment for Closed Transfer from Fermenter to Keg

• Pressure capable fermenter - like the FermZilla or Apollo
• A keg - most homebrewers opt for a 19L cornelius (corny) keg
• CO2 gas bottle with regulator, tubing and gas ball lock disconnect
• Beer transfer line with liquid ball lock disconnects on each end
  
  

  

  Keg King's Apollo plastic fermenter is a entry level fermenter that can be used for pressure transfers

Step-by-Step Guide to Closed Transfer for Homebrewers

1. Make sure your keg is cleaned, sanitised and pre-pressurised with 10psi of CO2.
   
   
2. Pressurise the fermenter with the same amount of pressure (in this case, 10psi). You can equalise the pressure between the vessels by connecting a gas to gas connection from the fermenter gas post to the keg gas post (but disconnect this when done and continue with the instructions below).
   
   Pro Tip: pre-purge your CO2 gas line before connecting to ensure there isn't any oxygen within it to avoid introducting it into your keg or fermenter.
   
   
3. Leave the pressure on your CO2 bottle regulator to 10psi with the gas open/on.
   
   
4. Connect your liquid/gas lines as outlined below (refer to diagram for corresponding numbers)
   * CO2 gas cylinder/regulator (1) to gas input of fermenter (2)
   * Liquid Out of fermenter (3) to Liquid Out post on keg (4)
   * Spunding valve (fully closed) connected to Gas In post on keg (5)
   
   Pro Tip: The liquid transfer line likely has some air/oxygen within it (unless you have pre-purged it with CO2), so we usually depress the ball lock disconnect on the keg side and bleed the first little bit of beer into a bucket (not the keg) to avoid any issues with oxygen contact from the air in the line. After doing this, connect it back to the ball lock post on the keg (4) and continue on.
   
   
   
   
   
5. Begin slowly unwinding the adjustment on the spunding valve until you can hear gas escaping. The transfer of beer should now be underway.
   
   
6. The process can be quite slow - but hey, what's the hurry? Taking it slow will help to reduce foaming in the keg. 
   
   
7. If your keg is at room temperature (or at least warmer than the beer being transferred into it) - you should be able to see frost forming on the outside of the keg showing the current fill level - see item 6 in the photo above.
   
   
8. You can speed up the process if necessary by further reducing the pressure in the keg (by pulling the pressure release valve or opening the spunding valve further).
   
   Alternatively, you can increase the pressure from the CO2 bottle to increase the difference in pressure between the vessels to speed up the transfer rate.
   
   
9. To stop the process, disconnect the liquid line between the keg and the fermenter.

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