De'Longhi EC155 Not Working? 8 Fixes (No Coffee, Loud Pump)

What Makes the EC155 Different

When a De'Longhi EC155 gives no coffee, or the espresso only drips, start with the tank and the filter. A tank that isn't pushed down keeps its valves shut, so the pump buzzes and nothing comes out. The EC155's filters also come apart into a cap, metal filter, gasket and plastic disk, and De'Longhi wants them cleaned every 200 espressos or as soon as the flow drops.

That take-apart filter is what sets the EC155 apart from De'Longhi's other small pump machines. So does a second filter inside the boiler outlet, which you unscrew with a screwdriver every 300 coffees. De'Longhi says skipping either job invalidates the warranty, and both are easy to miss because the machine never asks for them. There's no display, no error code and no descale light. You get one selector knob (Off, ON, coffee and steam), a separate steam knob, an ON light and a READY light.

Everything below comes from De'Longhi's own EC155M instruction book, the one on De'Longhi's US support page. If you own the ECP3420, ECP3220 or ECP3630, use that guide instead: its filters and cleaning schedule are different.

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Try This First

• Push the water tank down after every refill. De'Longhi says this opens the valves in its base. A tank sitting slightly high is the classic cause of a loud pump and no coffee.
• Check the water level. The book says to top up when it falls to about an inch (2 cm) from the bottom.
• Wait for the READY light before turning the selector to coffee. Brewing before it lights gives cold espresso.
• Just frothed milk? The boiler is at steam temperature. Cool it before brewing (Fix 5).
• Water in the space under the tank? De'Longhi says that's normal. Dry it with a sponge now and then.

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Which Fix You Need

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Fix 1: Fill and Seat the Tank (Works About 25% of the Time)

The water tank has valves in its base that open only when the tank is pushed fully home. De'Longhi's troubleshooting table gives two causes for an excessively noisy pump that are this simple: an empty tank, and a tank that isn't correctly in place, so the valve in its base stays shut.

Signs it's this one: a loud buzz and no coffee, often just after you lifted the tank out to fill it.

1. Turn the selector to O (off).
2. Open the tank lid and lift the tank straight up and out.
3. Fill it with fresh water, no higher than MAX.
4. Put it back and push it down, so the valves in its base open.
5. Turn the selector to ON, wait for READY, then try a short run with the selector on the coffee position.

Time: 2 minutes
Cost: Free
Success Rate: About 25%
Difficulty: Easy

You can also fill the tank in place by pouring from a jug, which avoids disturbing it at all.

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Fix 2: Clear the Air and Prime the Machine (Works About 20% of the Time)

If the tank is full and seated but the pump still roars, air is probably trapped in the tank connector. De'Longhi's answer is to run the hot water function until water comes through. Its first-use setup does the same job more thoroughly, and the book recommends it after the machine has stood unused for 3 to 4 days.

Signs it's this one: a new machine, one that's been unused, or one you let run dry.

Quick version (the troubleshooting table's fix):

1. Turn the selector to ON and wait for the READY light.
2. Put a cup under the steam wand.
3. Turn the selector to the coffee position and, at the same time, turn the steam knob counter-clockwise. Hot water comes out of the wand.
4. Stop when water flows steadily: steam knob clockwise, selector back to ON. Don't run hot water for more than 60 seconds at a time.

Full prime (De'Longhi's setup routine):

1. Selector on ON. Fit a filter in the holder and attach it without coffee.
2. Put a container of at least 17 oz (0.5 l) under the holder and another under the wand.
3. When READY lights, turn the selector to coffee and let about half the tank run out through the holder.
4. Turn the steam knob counter-clockwise and let the rest run out of the wand.
5. Close the steam knob, selector to ON. Empty the containers, refill the tank and repeat once.

Time: 5-10 minutes
Cost: Free
Success Rate: About 20%
Difficulty: Easy

⚠️ Safety: water and steam from the wand are scalding. Keep your hand off the wand and hold the container by its handle. The book's instruction is to repeat until water is delivered.

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Fix 3: Get the Dose and Tamp Right (Works About 15% of the Time)

On the EC155, how hard you press the coffee sets the speed of the shot. De'Longhi spells it out: press too hard and "coffee delivery will be slow and the crema will be dark"; press too lightly and it runs too fast, with skimpy, pale crema. Its list of causes for slow coffee also includes too much coffee, a grind that's too fine or damp, and the wrong type of coffee.

Signs it's this one: shots that only drip, or that gush in a few seconds, with a clean filter and a full tank.

1. Check the filter is empty of old grounds before you fill it.
2. One coffee: small filter, one level measure (about 7 g / 0.25 oz).
3. Two coffees: large filter, two loosely filled measures (about 6 g + 6 g), added a little at a time.
4. Spread the coffee evenly and press lightly with the tamper.
5. Wipe stray coffee off the rim, attach the holder and turn it firmly to the right. De'Longhi says this is what stops water leaking out.
6. Use pre-ground coffee made for espresso machines, and keep it dry. If it still drips, try a different coffee.

Time: 5 minutes
Cost: Free
Success Rate: About 15%
Difficulty: Easy

ESE pods: the small filter takes ESE-standard pods. Centre the pod, turn the holder as far as it will go, and preheat first (Fix 5).

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Fix 4: Take the Filter Apart and Clean It (Works About 15% of the Time)

The EC155's filter isn't a plain basket. It's an assembly: a metal filter and a gasket on a plastic disk, held in a steel container by a screw-on cap. Fine coffee packs into the metal filter's holes and the flow slows to a drip. De'Longhi wants it cleaned about every 200 espressos, or when the espresso drips out of the filter holder or not at all, and says skipping this invalidates the warranty.

Signs it's this one: flow that faded gradually, or a drip from the spouts even with a light tamp.

1. Lift the filter out of the filter holder. Clean the inside of the holder by hand. It must never go in a dishwasher.
2. Unscrew the filter cap in the direction of the arrow printed on it.
3. Push the filter out of its container from the cap end.
4. Take off the gasket.
5. Rinse every part. Scrub the metal filter in hot water with a brush, and clear any blocked holes with a pin.
6. Put the filter and gasket back on the plastic disk, with the pin on the disk through the hole in the gasket.
7. Drop the assembly back into the steel container, with the pin in the hole in the support, and screw the cap back on.

Time: 10 minutes
Cost: Free
Tools: a small brush and a pin
Success Rate: About 15%
Difficulty: Easy

Common mistake: putting the gasket back without lining up the pin. The pins only line up one way, so take a photo before you start. While the holder is apart, check the holes in its spouts too: blocked spout holes are on De'Longhi's list for both "no espresso" and drips from the holder's edges.

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Fix 5: Preheat for Hot Coffee, Cool Down After Steaming (Works About 10% of the Time)

The same boiler makes coffee and steam. Brew before READY lights, or into a cold holder and cup, and the espresso comes out lukewarm. Brew straight after frothing and the boiler is far too hot: De'Longhi says the coffee "will be burnt".

Signs it's this one: lukewarm espresso, or a harsh, burnt shot right after you steamed milk.

For hotter coffee:

1. Selector on ON, empty holder attached, the cup you'll drink from underneath.
2. When READY lights, turn to the coffee position and let water run until READY goes off. Turn back.
3. Empty the cup, wait for READY again, and repeat once. Then make your coffee.

After steaming:

1. Close the steam knob.
2. Take the holder off, put a container under the boiler outlet, turn the selector to coffee and let water run until READY goes off.
3. Return the selector to ON, then brew.

Time: 2-5 minutes
Cost: Free
Success Rate: About 10%
Difficulty: Easy

For several cappuccinos, De'Longhi's order is all the coffees first, then all the milk. A small puff of steam when you take the holder off is normal.

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Fix 6: Clear the Frother's Three Holes (Works About 5% of the Time)

The EC155's cappuccino frother has three small holes. Dried milk blocks them, and then the wand hisses without frothing. De'Longhi's other causes of no froth are milk that isn't cold enough, and scale.

Signs it's this one: big bubbles or no foam at all, with cold milk and a READY light.

1. Release a little steam for a few seconds, then close the steam knob.
2. Wait several minutes for the steam tube to cool.
3. Unscrew the frother by turning it clockwise, and wash it in warm water.
4. Check the three holes are clear. Use a pin if they aren't.
5. Wipe the steam tube, then screw the frother back on.

Time: 5 minutes
Cost: Free
Success Rate: About 5%
Difficulty: Easy

For froth, use about 100 g (3.5 oz) of milk per cappuccino straight from the fridge. De'Longhi recommends 2%. Start with the frother about 5 mm under the surface, go deeper once the milk has doubled, and stop at about 140°F (60°C). Steam for no more than 60 seconds, and don't froth more than three times in a row.

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Fix 7: Clean the Boiler Outlet Filter (Works About 5% of the Time)

Water leaves the boiler through a small filter in the outlet that the filter holder locks onto. Coffee residue and scale can block its holes, and De'Longhi lists a blocked boiler outlet for both "no espresso" and "coffee drips too slowly". The book asks you to clean it about every 300 coffees. This is the only cleaning job that needs a tool.

⚠️ Safety: unplug the machine and let it cool fully first. De'Longhi says it must not be hot.

1. Unplug the machine and let it cool.
2. Using a screwdriver, unscrew the screw that holds the boiler outlet filter, and take the filter off.
3. Clean it in hot water with a brush.
4. Clear any blocked holes with a pin.
5. Refit the filter and its screw.

Time: 15 minutes, plus cooling
Cost: Free
Tools: a screwdriver, a brush and a pin
Success Rate: About 5%
Difficulty: Moderate

That's as far into the machine as De'Longhi goes. Don't remove the outer cover: the book says doing so voids the warranty.

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Fix 8: Descale Every 200 Coffees (Works About 5% of the Time)

Scale is on De'Longhi's list for no espresso, cold espresso and no froth. The book recommends descaling about every 200 coffees with De'Longhi's descaler. There's no descale light on the EC155, so keep count yourself.

Signs it's this one: flow, heat and froth all fading slowly, with no descale in months.

1. Fill the tank to MAX with descaler diluted as the pack says.
2. Turn the selector to ON. Take the filter holder off, and put a container under the steam wand.
3. When READY lights, turn the selector to coffee and run out about a quarter of the tank. Open the steam knob now and then to release steam.
4. Turn back to ON and leave it for about 5 minutes.
5. Repeat steps 3 and 4 three more times, until the tank is empty.
6. Rinse the tank, fill it with clean water and run it all through. Then rinse a second time.

Time: About 40 minutes
Cost: De'Longhi descaler, about $10-15 a bottle
Success Rate: About 5%
Difficulty: Easy

Coffee tasting acidic afterwards means the rinse wasn't thorough enough, De'Longhi says. Run another tank of clean water. Our De'Longhi descaling guide has the methods for De'Longhi's other machines.

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When DIY Won't Work

Stop and contact De'Longhi Customer Services if:

• The pump runs loudly and no water comes through after Fixes 1, 2, 7 and 8.
• Espresso keeps leaking from the edges of the holder when it's clean and turned fully home. De'Longhi blames the espresso boiler gasket losing its elasticity, and says Customer Services should replace it.
• The ON light won't come on in an outlet that works.
• Water spreads under the machine beyond the small, normal puddle in the space under the tank.

Warranty: De'Longhi's book says not to remove the cover, and that trying to repair or modify the machine voids the warranty. It also says the filter and boiler-outlet cleaning in Fixes 4 and 7 is a condition of the warranty. It prints no warranty length or phone number, so start a claim through De'Longhi's US support site, delonghi.com.

Repair or replace? Online repair threads cover pump and valve replacements on the EC155, but those happen inside the housing. Inside warranty, let De'Longhi handle it. Outside it, compare a repair-shop quote with the price of a new machine before you pay for one.

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Prevention

Never use metal tools, solvents, abrasive cleaners or alcohol on the machine, and never immerse it. The book also warns against installing it where it could freeze, because frozen water inside can damage it.

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FAQ

Is water under the EC155's water tank normal?

Yes. De'Longhi's book says it's normal for water to collect in the space under the tank, and asks you to dry it regularly with a clean sponge. A puddle spreading across the counter is different. That points to a leak to report to De'Longhi.

Can I put the EC155's parts in the dishwasher?

Not the filter holder: the book says never to wash it in a dishwasher. De'Longhi's US product page describes the drip tray as dishwasher safe. Clean the filters, frother and tank by hand as the book describes.

Why does my EC155 make burnt coffee after a cappuccino?

The boiler is still at steam temperature. De'Longhi says to run water through the holder until the READY light goes off before brewing again, and to make all the coffees before frothing any milk.

How much water does the EC155 hold?

De'Longhi's US product page lists a removable 35 oz tank. Top it up when the level drops to about an inch (2 cm) from the bottom, and never run the machine dry.

Does the EC155 have a reset or error codes?

No. De'Longhi's book has no reset, no error codes and no descale alert for the EC155. Its two lights mean on, and ready (at temperature for coffee or for steam). Problems are worked out from the troubleshooting table, which is what this guide follows.

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Related De'Longhi Guides

• De'Longhi ECP3420 Not Working?: the ECP3220, ECP3420 and ECP3630 pump machines
• De'Longhi BCO430 Not Working?: the drip-and-espresso combination machine with the same take-apart filter
• De'Longhi Slow Brewing: slow flow across De'Longhi models
• De'Longhi Leaking Water Underneath?: leaks on De'Longhi machines
• De'Longhi Error Lights & Symbols: the bean-to-cup machines' warning lights

Sources: De'Longhi Instructions for use, EC155M (English, De'Longhi US support asset 222430); De'Longhi US product page for the EC155M.