Common Delong Coffee Machine Faults and Fixes

If your Delong coffee machine isn’t brewing, flashing red lights won’t go away, or it’s displaying cryptic error messages, you’re not alone. These issues crop up often—whether it’s a misaligned part, lack of water or beans, or just routine descaling needed. Let’s walk through the real causes and how to fix them properly.

The most common Delong coffee machine problems include a blinking or solid red light due to improperly installed parts, missing water or beans, and error codes like FILLWATER or DESCALEMACHINE. Most can be solved in under a minute by checking installation, refilling, or cleaning.

Why Is My Delong Coffee Machine Flashing a Red Light?

A blinking red light on your Delong machine usually means something isn’t seated correctly. The most frequent cause is the brew group base, water tank, or used coffee grounds container not being fully locked into place. To fix it, simply remove and then correctly reinsert each component. Make sure everything clicks into position securely.

What Does a Solid Red Light Mean on a Delong Coffee Machine?

A solid red light typically signals either low water or no coffee beans. First, turn off the machine, then add both water and beans. Restart the machine. If the red light stays on despite having water and beans, try draining the steam boiler: turn the steam knob to release any trapped water in the steam wand’s pipe.

Why Isn’t the Green Light Turning On?

If the green power or ready light isn’t on, check two things: whether the machine is properly plugged in, and whether the front door (if your model has one) is fully closed. Reconnect the power cord and ensure the door is shut tightly to restore normal operation.

How Often Should You Descale a Delong Coffee Machine?

Descaling is needed every 4 to 6 months, or sooner if you notice reduced water flow or the machine runs cooler than usual. Scale buildup comes from minerals in your water. For descaling, always use a commercial coffee machine descaler—do not use vinegar, as it can damage internal components.

Why Is My Delong Coffee Machine Brewing Slowly or Weakly?

Slow or difficult espresso extraction is usually caused by incorrect grind size. Coffee that’s too fine can clog the filter, while coffee that’s too coarse leads to fast, weak extractions. Adjust your grinder to a finer or coarser setting until you reach the right flow rate—typically a 25 to 30 second extraction for a double shot using around 20 grams of coffee to produce 40 grams of espresso.

Common Delong Coffee Machine Error Codes and What They Mean

FILLWATER

This means the water tank is empty or the float valve inside is faulty. Refill the water tank. If the issue continues, try wiping the float or descaling the tank to clear any blockage.

FILLBEANS

This code shows when the bean hopper is empty—or sometimes lingers even after adding beans. Add more coffee beans. The message should disappear after brewing a shot.

EMPTYGROUNDS

The used coffee grounds (puck) container is full, or it was reinserted too quickly after emptying. Empty the grounds tray, then wait 10 seconds before putting it back in.

DRAWERMISSING

This means the coffee puck drawer (grounds container) isn’t installed or isn’t seated properly. Check that it’s in place and reinsert it firmly until it locks.

CLEANMACHINE / MACHINEREADY

Your machine needs a thorough cleaning, likely because the brew group or internal pathways need flushing. Run the cleaning cycle as instructed in your manual.

DESCALEMACHINE / MACHINEREADY

This signals that internal scale buildup requires descaling. Use a proper coffee machine descaling solution and follow the manufacturer’s steps to protect your machine’s heating elements and pipes.

CHANGEFILTER / MACHINEREADY

A water filter (if your model includes one) needs replacing. Install a fresh filter according to the manufacturer’s guidelines.

ERROR

This generic fault code means the machine has encountered an internal issue. Turn the machine off, unplug it from power for a minute, then plug it back in and restart. This often resets minor electronic faults.

Frequently Asked Questions

Why is my Delong coffee machine’s red light blinking non-stop?

A continuously blinking red light usually means the brew group base, water tank, or coffee grounds container isn’t properly installed. Remove each part and reinsert it until it clicks or locks securely into place.

What should I do if the red light on my Delong machine stays on even with water and beans?

If the red light remains on despite having water and beans, the steam system may have trapped water. Turn the steam knob to release any leftover water in the steam wand’s pipe, then restart the machine.

How do I fix a Delong coffee machine that won’t turn on or shows no green light?

Check that the machine is plugged in properly and that any front door is fully closed. Reconnect the power supply and ensure the door is shut to restore the green ready or power light.

What causes slow espresso extraction on a Delong machine?

Slow shots are usually due to coffee ground too fine, causing over-extraction and clogging. Try adjusting your grinder to a slightly coarser setting for better flow—ideally aiming for a 25–30 second extraction time.

What does the FILLWATER error code mean on my Delong coffee machine?

FILLWATER means the water tank is empty or the internal float valve is stuck. Refill the tank and check the float mechanism. If the problem persists, consider descaling the water system.

Do I really need to descale my Delong coffee machine every 4–6 months?

Yes. Mineral deposits from water build up over time and reduce performance. Descaling every 4 to 6 months—or sooner if flow slows or temperature drops—helps maintain proper function and extends machine life.

Can I use vinegar to descale my Delong coffee machine?

No. The manufacturer specifically warns against using vinegar. Always use a proper coffee machine descaling solution to avoid damaging internal components.

Recommended FrontStreet Coffee Beans for Home Espresso

For home espresso machines like your Delong, try FrontStreet Coffee’s Classic Blend for balanced notes of caramel and nuts, or Specialty Blend for brighter tones with hints of citrus and dark cherry. Both are freshly roasted for optimal extraction and designed to perform well under standard home machine pressure. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.