Closed Transfer Line Kit | Fermenter-to-Keg Beer Transfer

Oxygen-Reduced Beer Transfer from Fermenter to Keg

Transfer finished beer from a pressure-capable fermenter into a ball lock keg while keeping the system closed with this ready-to-use closed transfer line kit.

The kit includes two liquid ball lock disconnects joined by two metres of large-bore EVA Barrier tubing. Connect one end to the liquid post of your pressure fermenter and the other to the liquid post of a purged receiving keg.

A controlled pressure difference moves the beer without exposing it to unnecessary oxygen, helping preserve hop aroma, flavour and freshness.

Why You’ll Love It

• Transfers beer from a pressure fermenter to a ball lock keg

• Helps reduce oxygen exposure during packaging

• Ideal for hoppy beer and oxygen-sensitive styles

• Includes two liquid ball lock disconnects

• Includes two metres of large-bore transfer tubing

• Fast transfer through 6.3mm internal-diameter line

• Ready to connect to compatible liquid posts

• Suitable for FermZilla and similar pressure fermenters

• Can also be used for closed keg-to-keg transfers

• Reusable and easy to clean

Why Use a Closed Transfer Line?

Oxygen exposure after fermentation can quickly reduce hop aroma, darken beer and create stale flavours.

A closed transfer moves the beer through sealed tubing from the fermenter into a purged keg. This reduces contact with the surrounding air and helps retain the beer’s intended flavour, aroma and colour.

Closed transfers are particularly valuable for:

• Hazy IPA and NEIPA

• American IPA

• Pale ale

• Dry-hopped beer

• Delicate lager

• Beer intended for extended storage

• Any beer sensitive to post-fermentation oxidation

What’s Included?

Each closed transfer line includes:

• Two 9.5mm Duotight liquid ball lock disconnects

• Two metres of EVA Barrier transfer line

• Tubing dimensions: approximately 6.3mm ID × 9.5mm OD

• Fully assembled fermenter-to-keg transfer line

Specifications

• Product type: Closed beer transfer line

• Transfer direction: Liquid post to liquid post

• Disconnect type: Ball lock liquid

• Number of disconnects: Two

• Tubing material: Double-wall EVA Barrier

• Tubing length: Approximately 2 metres

• Tubing internal diameter: Approximately 6.3mm

• Tubing outside diameter: Approximately 9.5mm

• Application: Pressure fermenter to keg or keg-to-keg transfer

• Gas equipment: Not included

• Spunding valve: Not included

Equipment Required

To perform a controlled closed transfer, you will also need:

• A pressure-rated fermenter with a liquid ball lock post

• A compatible ball lock receiving keg

• A regulated CO₂ supply

• A spunding valve or another safe method of controlling receiving-keg pressure

• Sanitiser and suitable brewery cleaner

Only use pressure-rated equipment and remain within the manufacturer’s stated pressure limits.

How to Perform a Closed Transfer

1. Clean and sanitise the transfer line, disconnects and receiving keg.

2. Purge the receiving keg with CO₂ to reduce the amount of oxygen inside it.

3. Apply approximately 3–5 PSI to the receiving keg.

4. Attach a spunding valve to the receiving keg’s gas post.

5. Apply approximately 5 PSI to the pressure fermenter.

6. Connect one liquid disconnect to the fermenter’s liquid post.

7. Connect the other liquid disconnect to the receiving keg’s liquid post.

8. Adjust the spunding valve to create a small pressure difference and begin the transfer.

9. Monitor the transfer and keep the system pressure stable.

10. Disconnect the line once the receiving keg has reached the required fill level.

The exact pressure required will depend on the fermenter, keg, beer temperature and system configuration. Use the lowest pressure that provides a smooth, controlled transfer.

How Do I Know When the Keg Is Full?

Placing the receiving keg on a suitable set of scales is the easiest way to monitor the transfer.

As a practical guide, one litre of beer weighs approximately one kilogram. Remember to account for the empty weight of the keg before beginning.

Do not completely fill the keg. Leave sufficient headspace for safe operation and carbonation.

Does This Kit Include a Gas Return Line?

No. This product is the liquid transfer line that connects the fermenter’s liquid post to the receiving keg’s liquid post.

A CO₂ supply, gas line and spunding valve are required separately for a controlled pressure transfer.

Will It Fit a FermZilla?

Yes. It can connect to a pressure-rated FermZilla fitted with compatible ball lock liquid posts or yellow liquid carbonation caps.

It may also suit other pressure fermenters fitted with compatible liquid ball lock connections.

Can It Transfer Beer Between Two Kegs?

Yes. The liquid-to-liquid configuration can be used for closed ball lock keg-to-keg transfers.

The source keg must be pressurised, and gas must be safely released or regulated from the receiving keg to allow the beer to flow.

Why Is My Beer Not Flowing?

Common causes include:

• Insufficient pressure difference

• The receiving keg not being vented

• A closed or incorrectly adjusted spunding valve

• The disconnect attached to the wrong post

• A blocked dip tube or floating dip-tube filter

• Kinked transfer tubing

• Sediment blocking the fermenter outlet

• Source and receiving vessels at equal pressure

Do not exceed the pressure rating of the fermenter, keg or fittings to force a blocked transfer.

How Can I Reduce Foaming?

For a smoother transfer:

• Chill the beer before transferring

• Keep the receiving keg cold

• Begin with both vessels at a similar pressure

• Create only a small pressure difference

• Avoid excessive transfer speed

• Transfer through the receiving keg’s liquid post

• Keep the transfer line free from sharp bends

How Do I Clean the Transfer Line?

Rinse the line immediately after use before beer residue can dry.

Circulate or push a suitable brewery cleaner through the line and disconnects, rinse thoroughly and sanitise before the next transfer. The disconnects can be disassembled when deeper cleaning is required.

Does a Closed Transfer Completely Eliminate Oxygen?

A properly purged and sealed system can greatly reduce oxygen exposure, but the final result depends on how thoroughly the receiving keg is purged and how well the system is sealed.

Check every fitting for leaks and avoid opening the receiving keg after purging.

Why Buy from Border Brewing Supplies?

Border Brewing Supplies assembles this closed transfer line for home brewers wanting a convenient, ready-to-use connection between their pressure fermenter and keg.

We supply pressure-fermentation and kegging equipment throughout Tweed Heads, the Gold Coast, Northern Rivers, Brisbane and the wider Queensland–New South Wales border region.

Shop online for Australia-wide delivery or select Click & Collect from our Tweed Heads South home brew shop.

Recommended Products

Complete your closed-transfer setup with:

• Ball lock keg

• Spunding valve with pressure gauge

• CO₂ regulator

• Duotight gas disconnect

• EVA Barrier gas line

• Floating dip tube and filter

• Brewery cleaner

• No-rinse sanitiser