Keg Is Full but Beer Won’t Pour: 9 Parts to Check First
If the keg is full but no beer comes out of the faucet, the problem is usually somewhere between the gas source and the dispense point.
Common causes include a closed gas valve, regulator issue, poorly engaged coupler, tripped FOB, blocked beer line, failed pump, or clogged faucet.
The fastest way to troubleshoot is to start at the gas source and follow the system toward the keg and faucet.
Key Takeaways
- Check gas supply and shutoff valves before changing pressure.
- If only one tap has failed, focus on that line rather than the entire gas system.
- A coupler or FOB can completely stop flow even when the keg is full.
- Slow flow and no flow usually have different causes.
- Do not increase PSI randomly to force beer through a restriction.
Before You Start: No Flow or Slow Flow?
| System Status | What to Check & Possible Causes |
|---|---|
| No Flow (If nothing comes out, check for:) |
|
| Slow Flow (If beer still reaches the faucet but moves slowly, possible causes include:) |
|
| Troubleshooting Scope |
|
1. Check the Gas Cylinder and Main Valve
Confirm that the gas cylinder is not empty and the main valve is open.
Check:
- cylinder contents
- valve position
- cylinder connection
- obvious leaks
- shared gas shutoffs
If several taps lose flow at once, the gas source is one of the first places to inspect.
Do not disconnect or loosen pressurized gas fittings during troubleshooting unless the system has been safely isolated.
2. Check the Regulator and Shutoff Valve
A cylinder can contain gas while nothing reaches the keg.
Inspect the CO₂ and nitrogen regulators and confirm:
- the regulator shows pressure
- the outlet shutoff is open
- secondary regulators are open
- gas tubing is connected
- pressure has not been turned down to zero
Do not assume low flow means the PSI simply needs to be increased. Correct pressure depends on beer temperature, carbonation, line resistance, and system design.
If the regulator appears normal, continue downstream rather than changing the setting repeatedly.
3. Make Sure the Keg Coupler Is Fully Engaged
The coupler connects the gas side of the system with the beer inside the keg. If it is not seated or locked correctly, the keg may remain full but no beer will move.
Check the keg coupler for:
- correct coupler type
- full engagement with the keg valve
- handle locked in the operating position
- secure gas and beer connections
- damaged or missing seals
If a newly connected keg will not pour, disconnect and reseat the coupler according to the manufacturer’s procedure.
Do not force a coupler onto a keg valve that does not match. Different keg systems require different coupler types.
4. Inspect the Coupler Check Ball and Internal Parts
If the coupler is engaged but beer still does not flow, inspect its internal components.
A check ball or valve can become stuck because of:
- dried beer
- debris
- worn seals
- damaged springs
- incorrect reassembly after cleaning
Compatible keg coupler parts can be used to replace worn seals, check balls, probes, and other service components when required.
Before disassembling the coupler, isolate and depressurize the system safely.
If buildup is visible, clean the removable parts according to the manufacturer’s instructions. A blocked internal valve can completely stop beer even when gas pressure and keg volume are normal.
5. Check the FOB Detector
In long-draw systems, a Foam-On-Beer detector may stop flow when a keg empties. After a new keg is connected, the FOB may remain closed until it is reset or vented correctly.
Inspect the FOB detector for:
- float position
- beer inside the chamber
- reset mechanism
- vent operation
- leaks or damaged seals
A closed FOB can make a full replacement keg appear as though it is not dispensing at all.
Do not bypass the detector just to restore flow. If it repeatedly trips with a full keg, inspect the surrounding pressure, coupler, and line conditions.
6. Inspect the Beer Line for Kinks or Blockage
Follow the product line from the keg toward the faucet.
Look for:
- sharp bends
- crushed or pinched tubing
- frozen sections
- visible buildup
- damaged hose
- lines trapped behind equipment
Restricted beer tubing and accessories can reduce flow or stop it completely.
If the line is only partially restricted, the beer may pour slowly rather than stop. Replace damaged tubing instead of repeatedly bending it back into shape.
A blockage that returns after cleaning may indicate a larger sanitation, freezing, or equipment problem elsewhere in the system.
7. Check the Faucet and Shank
If beer reaches the tower but does not exit normally, inspect the faucets and shanks.
Possible problems include:
- dried beer inside the faucet
- blocked vent holes
- seized internal parts
- debris in the shank
- damaged flow-control components
Remove and clean the faucet according to the manufacturer’s instructions. Do not increase pressure to force beer through a blocked faucet.
If the handle is difficult to move or the faucet has not been cleaned recently, buildup is a likely place to start.
8. Check the Beer Pump in Long-Draw Systems
This step only applies to systems that use a pump to move beer through longer runs.
Inspect the beer pump for:
- gas or air supply
- pump regulator
- inlet and outlet connections
- leaks
- damaged tubing
- whether the pump is cycling
A pump that is not receiving drive pressure may stop beer flow even when the keg itself is properly pressurized.
Do not increase pump pressure randomly. The pump must operate within the requirements of the equipment and overall draft-system design.
9. Inspect the Keg Valve and Seal
If the gas, coupler, FOB, line, faucet, and pump all check out, the problem may be the keg itself.
Possible issues include:
- damaged keg valve
- torn valve seal
- debris around the valve
- valve not opening fully
- packaging defect
One useful test is to connect the keg to a known-working compatible line. If that line also stops flowing, the keg valve becomes a stronger suspect.
Do not attempt to repair or modify a pressurized commercial keg valve. If the keg appears defective, isolate it and contact the distributor or brewery.
What If Beer Starts Flowing but It Is Mostly Foam?
Once beer begins moving again, excessive foam is a different troubleshooting problem.
Check:
- beer temperature
- applied pressure
- line balance
- coupler seal
- faucet cleanliness
- correct gas type
Do not keep increasing pressure simply because the system was previously blocked. Foam often points to temperature or balance rather than insufficient pressure.
Quick Troubleshooting Table
| Symptom | Check First |
|---|---|
| No taps pour | Gas cylinder and main valve |
| Only one tap does not pour | Coupler, FOB, line, or faucet |
| New keg will not pour | Coupler engagement and FOB reset |
| Beer pours very slowly | Pressure, restriction, or kink |
| Flow stops after keg change | FOB detector |
| Long-draw line has no flow | Beer pump |
| Faucet is difficult to operate | Faucet buildup or internal parts |
| Problem follows one keg | Keg valve or seal |
When to Stop Troubleshooting and Call a Technician
Professional service is the better option when:
This approach usually identifies the failure faster and reduces the risk of creating new pressure or carbonation problems while trying to restore flow.
- a CO₂ or gas leak is suspected
- regulator pressure changes unpredictably
- several taps repeatedly lose pressure
- the beer pump will not operate correctly
- a line appears frozen
- the keg valve may be damaged
- pressurized components require more than routine maintenance
- the problem returns after basic checks
Gas-system problems should be treated as safety issues, not just dispense problems.
Final Thoughts
When a full keg will not pour, troubleshoot in order rather than replacing parts at random:
This approach usually identifies the failure faster and reduces the risk of creating new pressure or carbonation problems while trying to restore flow.
FAQs
Why is my keg full but no beer comes out?
Common causes include a closed gas valve, regulator issue, improperly engaged coupler, tripped FOB, blocked line, clogged faucet, failed pump, or keg-valve problem.
Can a bad keg coupler stop beer from pouring?
Yes. An incorrect, damaged, or poorly engaged coupler can prevent gas from entering the keg or beer from leaving it.
Why does a new keg not pour after I connect it?
Check whether the coupler is fully engaged and whether the FOB needs to be reset after the previous keg emptied.
How do I know if a FOB detector needs to be reset?
The float may remain in the closed position after a keg change. Follow the detector’s reset and venting procedure before troubleshooting other downstream components.
Can a clogged beer line completely stop flow?
Yes. Severe buildup, frozen beer, crushed tubing, or a sharp kink can stop beer completely.
Why does my beer pump stop dispensing?
Possible causes include loss of drive pressure, a regulator problem, disconnected tubing, internal pump failure, or another restriction in the system.
Can a dirty faucet prevent beer from pouring?
Yes. Dried beer, debris, or seized internal parts can restrict or completely block the faucet.
Why does beer pour from other taps but not one faucet?
If the other taps work normally, focus on the individual line: coupler, FOB, beer tubing, faucet, and any dedicated pressure control for that product.