DeLonghi La Specialista Arte Not Working? 5 Fixes (EC9155)

Read the Lights Before You Take Anything Apart

A La Specialista Arte that won't brew is usually telling you why. The EC9155 has no error codes, so its lights do the talking. A flashing water light while you brew means one of five things: an empty tank, a grind that's too fine, a clogged filter basket, a tank whose valves aren't open, or scale. Most of those take under five minutes to fix.

The Arte is a manual espresso machine with a grinder built in. You grind straight into the portafilter, tamp by hand with the supplied tamper, lock the portafilter into the brewing unit and press OK. There is no Smart Tamping Station, no tamping lever and no "ATS" light on this model. Those belong to other La Specialista machines, and fixes written for them won't match your control panel. One thermoblock heats the water for both coffee and steam.

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Try This First

• Check the main switch on the side. It has to be in the I position. With the switch on and the machine asleep, press OK to wake it. The Arte turns itself off after the time set in its menu: 9 minutes, 1.5 hours or 3 hours.
• Press the water tank down. The valves on its base only open when it's properly seated. A steady water light means the tank is low or not inserted correctly.
• Look for OK lit on its own. That means the coffee or steam circuit is empty, which happens on first use or after the tank ran dry. Put a container of at least 3.4 fl oz (100 ml) under the hot water spout and press OK to refill it.
• Match the filter basket to the 1X/2X light. Grinding with the 2X light on into the single basket overfills it. De'Longhi's manual lists this as the reason a portafilter won't lock in.
• Ignore water in the drip tray. De'Longhi says the Arte discharges small amounts there during normal use. Empty it regularly.

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La Specialista Arte Warning Lights: What Each One Means

These come from the lights table in De'Longhi's EC915X instructions, read from the rendered pages.

A drink light that blinks orange while you hold OK isn't a fault either. It means you're programming that drink's quantity.

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Fix 1: Clear the Flashing Water Light (Works About 35% of the Time)

When the water light flashes during a shot, the machine is pushing water and not getting enough through. De'Longhi lists five causes for that light and the same five under "No espresso coffee is delivered". Work through them in order, cheapest first.

Signs it's this one: the water light flashes, and coffee comes out a few drops at a time or not at all.

1. Fill the tank to MAX and press it down lightly so the valves on the bottom open.
2. If only the OK light is on, press OK to refill the circuit, with a container under the hot water spout.
3. Remove the portafilter. If the coffee dripped out slowly and the puck is dense, the grind is too fine. Go to Fix 2.
4. Knock out the puck and rinse the filter basket under plenty of running water. Hold it up to the light: every hole should be clear.
5. Brew again. If the light still flashes with a full tank and a clean basket, scale is the likely cause. Go to Fix 4.

Time: 5 minutes
Cost: Free
Success Rate: About 35%
Difficulty: Easy

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Fix 2: Reset Your Dose and Grind (Works About 30% of the Time)

The Arte has two grinding controls, and they're easy to mix up. The grinding level selector on the machine sets how fine the coffee is. The coffee dose dial on the control panel sets how much it grinds. The dose dial's numbers aren't grams, grind settings or seconds. De'Longhi calls them a reference point once you've found the right dose.

Signs it's this one: the portafilter won't lock in (too much coffee), the shot drips with very dark crema (too fine), or it gushes pale and fast (too coarse).

1. Press the 1-or-2-cups button until its light matches the basket you're using.
2. Set the grinding level. The factory setting is 5, and De'Longhi recommends 3 to 6 for most coffees. Turn the selector only while the grinder is running.
3. Fit the dosing funnel, then push the portafilter into the grinder outlet until you hear one click. Grinding starts and stops by itself. Push again to stop it early.
4. Tap the funnel to level the coffee, tamp, and lift the funnel off. The tamped coffee should sit at the "perfect dose" mark inside the basket. Turn the dose dial up or down until it does.
5. Only once the dose is right, adjust the grind. A slow, over-extracted shot needs a coarser grind. A fast, pale one needs a finer grind.
6. If the dose dial is at maximum and the basket is still short, switch to the second grinding range. Hold the 1-or-2-cups and temperature buttons together for 3 seconds. Turn the mode dial to Americano, press the temperature button to choose the 2nd range, and press OK to save.

Settings 1 and 2 grind very fine. De'Longhi reserves them for light roasts, or for grinders whose burrs have worn.

Time: 10-20 minutes, including test shots
Cost: A few doses of beans
Success Rate: About 30%
Difficulty: Easy

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Fix 3: Unblock a Grinder That Runs But Nothing Comes Out (Works About 15% of the Time)

If you can hear the motor but the basket stays empty, the grinder or its funnel is clogged, or there's something in the beans it can't grind. De'Longhi's remedy is to open the grind all the way up and empty the hopper completely.

Signs it's this one: the grinder runs, but little or no coffee lands in the basket.

⚠️ Safety: switch off at the main switch and unplug before a vacuum nozzle or brush goes near the grinder.

1. Turn the grinding level selector to 8.
2. Switch off and unplug the machine.
3. Vacuum every bean and fragment out of the bean container until it's empty and clean.
4. Use the supplied cleaning brush on the grinder outlet, where the portafilter attaches, and on the coffee funnel.
5. Plug in, refill with fresh beans and grind into the portafilter. Bring the selector back to your usual setting while the grinder is running.
6. If it still runs empty or stalls, stop. The manual offers no owner repair beyond this, so contact De'Longhi Customer Service.

Changing beans works the same way. Load only the beans you plan to use, and grind or vacuum the hopper empty before you pour in a new coffee.

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

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Fix 4: Descale When the Descale Light Turns Red (Works About 12% of the Time)

Scale narrows the water path through the thermoblock, which is why it appears on both the flashing-water-light list and the "no espresso" list. The descale light turns steady red when a cycle is due. The whole cycle takes about 40 minutes, including the rinse.

Use De'Longhi descaler only. The manual warns that unsuitable descaler, or descaling incorrectly, can cause faults the guarantee doesn't cover.

1. Pour the descaler into the empty tank up to level A marked inside (one 100 ml packet). Add water up to level B (1 liter) and refit the tank.
2. Turn the mode dial to the descaling position. The OK light turns orange and the descale light flashes.
3. Take the portafilter off. Put a container that holds about 2 liters under the brewing unit, the hot water spout and the steam wand.
4. Hold OK for at least 3 seconds. Descaler runs through the steam wand and brewing unit in a series of rinses and pauses until the tank is empty.
5. When the OK light turns white, empty the container. Rinse the tank and fill it with fresh water to MAX.
6. Put the container back and press OK to rinse. When delivery stops, empty the container and the drip tray, and refill the tank.

If the machine asks for another rinse at the end, the tank wasn't filled to MAX for the first one. Refill it and finish the rinse. If you started descaling by mistake, holding OK for 10 seconds stops it. The rinse can't be stopped.

Time: About 40 minutes
Cost: Free with the packet in the box, then De'Longhi descaler
Success Rate: About 12%
Difficulty: Easy

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Fix 5: Stop Espresso Dripping From the Portafilter Edges (Works About 8% of the Time)

Coffee running down the outside of the portafilter instead of from the spouts usually means it isn't locked in properly. De'Longhi's service documentation adds a third cause that isn't an owner fix: a worn or dirty espresso boiler gasket.

1. Align the portafilter handle with INSERT, then turn it firmly to the right to CLOSE, as far as it will go.
2. Rinse the filter basket under running water. If it clogs again quickly, grind one step coarser.
3. If coffee still escapes around the rim with the portafilter fully closed and a clean basket, the gasket has likely lost its elasticity. De'Longhi's service sheet says to have it replaced by Customer Services.

Water under the machine rather than around the portafilter is a different problem. See the La Specialista leaking guide.

Time: 5 minutes
Cost: Free (a gasket replacement is a service job)
Success Rate: About 8%
Difficulty: Easy

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Arte or Another La Specialista?

Check the model code on the label before you follow any La Specialista guide. The machines look alike but work differently.

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When DIY Won't Work

Stop and contact De'Longhi if:

• All three temperature lights keep flashing. That's the general alarm, and the manual's only instruction is to call Customer Service.
• The grinder still runs empty after Fix 3.
• The basket never reaches the perfect dose, even at maximum on the second grinding range. De'Longhi says burrs wear over time and a Customer Service Centre changes them.
• Coffee leaks from the portafilter rim after Fix 5 (gasket).
• You smell burning, the breaker trips, or water pools under the machine near the power cord. Unplug it and stop using it.

Warranty: De'Longhi's instructions say not to remove the machine's exterior or attempt repairs, as that voids the warranty, and that repairs are for authorized service personnel only. Find a service center through delonghi.com; De'Longhi's US support page for this model is delonghi.com/en-us/s/EC9155MB.

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Keeping an Arte Brewing

• Descale when the light turns red, and set the water hardness in the menu with the test strip from the box so the reminder comes at the right interval.
• Load only the beans you'll use soon, and grind the hopper empty before switching coffees.
• Brush the grinder outlet and funnel as part of your cleaning routine. It's De'Longhi's own grinder cleaning step.
• Wipe the steam wand after every use. Once it's cool, clear the nozzle hole with the cleaning needle.
• Hand-wash the portafilter, filters and tank. De'Longhi's cleaning chart doesn't allow them in the dishwasher. Only the drip tray and grilles can go in. Wipe the bean container with a cloth.
• Run a rinse cycle before using the machine after more than a week unused.

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FAQ

Does the La Specialista Arte have error codes?

No. It uses lights only, and none of them shows a number. The one to take seriously is the general alarm: the MIN, MED and MAX temperature lights flashing together. De'Longhi's instruction for that is to contact Customer Service.

Why is the OK light orange?

The mode dial is on the descaling position. OK stays orange while descaling is selected or running, then turns white for the rinse. Turn the dial back to a drink if you selected it by accident.

Can I descale the La Specialista Arte with vinegar?

No. The manual says to use De'Longhi descaler only, and warns that unsuitable descaler can cause faults the manufacturer's guarantee doesn't cover.

How do I reset the Arte to its default settings?

Hold the 1-or-2-cups and temperature buttons together for 3 seconds to open the menu, then hold the steam button for 3 seconds. That restores De'Longhi's default values for the menu settings, such as pre-infusion, grinding range, auto-off and water hardness. It's a settings reset, not a repair.

What grind setting should I use?

Start at 5, the factory setting. De'Longhi recommends 3 to 6 for most coffees. Change it only while the grinder is running, and get the dose to the basket's mark before you judge the grind.

Why won't the portafilter lock in after grinding?

There's too much coffee in the basket. Usually the 2X light was on with the single basket, or the dose dial is set too high. Grind again with the right cup setting and a lower dose.

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Related De'Longhi Guides

• La Specialista warning lights, all five models
• De'Longhi grinder cleaning and maintenance: what the manuals actually ask you to clean
• La Specialista leaking water
• De'Longhi error codes and warning lights: the Magnifica, Dinamica and Dedica light tables
• La Specialista Arte vs Prestigio
• De'Longhi descaling guide

Sources: De'Longhi EC915X (La Specialista Arte) Instructions for use, US/Canada edition (5713250633_00_0621); De'Longhi Data Sheet and Service Manual, EC9155 La Specialista Arte (DSDL_21010_A).