What Causes Foamy Beer From a Tap (And How to Fix It)

There’s nothing worse than pulling a pint that turns into foam. It wastes product, slows service, and frustrates everyone. If you’re dealing with that behind the bar, here’s what’s really going on—and how to fix it for good.

1. Temperature Problems

Warm beer is foamy beer. If your walk-in cooler or glycol system isn’t holding steady around 36–38°F, CO₂ escapes from the beer before it reaches the tap. That gas expansion creates foam every time you pour.

Check that your refrigeration system is properly maintained and that glycol lines are cooling consistently. Temperature fluctuations are the number-one culprit we see on service calls.

For more technical standards, see the Brewers Association Draft Beer Quality Manual.

2. Incorrect Gas Pressure

Your gas regulator controls how much CO₂ stays in the beer.

• Too high: CO₂ over-absorbs, then escapes violently when poured.
• Too low: The beer goes flat in the line, creating uneven, gassy pours.

Our team adjusts regulators during preventative maintenance visits to match each beer style and system length.

3. Line Issues

If your beer lines are too short, too wide, kinked, or dirty, you’ll see foam. Line restriction keeps beer flow smooth, so when that balance is off, turbulence happens—and turbulence equals foam.

Routine draft line cleaning helps prevent buildup that causes bubbles and off-flavors.

4. Dirty or Worn Parts

Old faucets, couplers, or seals can create tiny leak points that cause foaming and flat beer at the same time. When we service a draft system, we replace worn seals and deep-clean every component so gas and beer flow evenly.

If you’re noticing more foam over time, schedule a full draft system check.

5. Over-Carbonated Kegs

Sometimes the issue starts before the beer ever reaches your bar. If a keg is over-carbonated at the brewery or stored too warm, you’ll get a geyser even if everything else is perfect. Always store kegs cold and upright.

The Bottom Line

Foamy beer usually means something simple: wrong temperature, bad pressure, dirty lines, or worn hardware. The good news? Every one of those is fixable.

For energy-efficient cooling standards, check the EPA Energy Star commercial refrigeration guide.

If you’re tired of wasting product, CBG can help diagnose and fix the issue fast. Book a service visit and we’ll make sure your next pour comes out clean, cold, and perfectly balanced.

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