DeLonghi La Specialista Maestro Not Working? 5 Fixes (EC9665)

The Maestro Tells You What's Wrong With Its Lights

When a La Specialista Maestro stops brewing, check which light is on before anything else. The water light and the triangle alarm flashing together is the most common case. It usually means an air bubble from the water softener filter, and pressing the hot water button clears it. A steady triangle on its own is the general alarm, which De'Longhi says needs Customer Services.

The Maestro (EC9665) is the La Specialista with the LatteCrema milk system. It grinds into the portafilter at a Smart Tamping Station with a presser lever, like the Prestigio, and adds automatic milk drinks, an Active Rinse button and a Descaling button. De'Longhi's manual for it doesn't mention "Sensor Grinding" or "Active Temperature Control". Its troubleshooting table is about water, dose, grind, milk and scale, and that's what the fixes below follow.

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Try This First

• Check the main switch on the back is at I, then press ON/Standby.
• Push the bean container until it clicks. A flashing "!" can mean it isn't fully locked, and the Maestro won't work until it is.
• Press the water tank down so its valves open.
• Check the grind selector is between 1 and 8. Outside that range, the "!" light flashes.
• Look at the milk-clean light. If it's on, the LatteCrema System wants its clean before the next milk drink.

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Maestro Warning Lights

From the lights table in De'Longhi's EC96XY instructions, read from the rendered pages:

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Fix 1: Clear the Water and Alarm Lights (Works About 30% of the Time)

The water light and triangle flashing together is the Maestro's flow warning. The first cause in the manual is specific to machines with a water softener filter fitted: an air bubble can be released inside the circuit and block delivery.

Signs it's this one: both lights flash when you try to brew, and little or no coffee comes out.

1. If a water softener filter is fitted, press the hot water button. Water runs through and stops by itself, clearing the bubble.
2. Fill the tank to MAX and press it down lightly so the valves open.
3. Remove the portafilter. A dense puck with a drip-by-drip shot means the grind is too fine. Make the dose again following the manual's grinding step.
4. Rinse the filter basket under running water, or use Active Rinse (Fix 5).
5. If it keeps flashing, descale (Fix 4).

Time: 5 minutes
Cost: Free
Success Rate: About 30%
Difficulty: Easy

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Fix 2: Clear the "!" Light (Works About 20% of the Time)

The "!" light guards the grinder. The Maestro won't grind with the bean container loose, or with the selector outside its 8 grind levels.

Signs it's this one: the grinder won't start and the "!" light is on or flashing.

1. Lift the bean container and push it back until the arrow lines up with the padlock symbol and it clicks.
2. Check the grind selector. Beyond level 8 is the REMOVE position used for cleaning the burr, and the "!" light flashes there.
3. Start grinding, then move the selector back within 1-8. Always adjust while grinding.
4. Change one level at a time and make at least 5 coffees before changing it again.

Time: 2 minutes
Cost: Free
Success Rate: About 20%
Difficulty: Easy

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Fix 3: Clean the LatteCrema System (Works About 20% of the Time)

The Maestro wants its milk system cleaned after every use, and the milk-clean light comes on to remind you. A dirty system is also one of the manual's causes of no milk froth, along with milk that isn't cold, the froth knob in the wrong position, and scale.

Signs it's this one: the milk-clean light is on, or milk drinks come out flat or thin.

1. Leave the milk container on the machine. There's no need to empty it. Put a cup under the milk spout.
2. Turn the froth knob to Clean. Cleaning starts and stops automatically.
3. Turn the knob back to a froth setting afterwards. It won't froth while it's left on Clean.
4. For a deeper clean, remove the container, press the lid release button, and take off the milk spout and intake tube. Scrape milk out of the groove under the knob with a toothpick and rinse the knob seat.
5. The lid parts and container are dishwasher-safe in the top basket. By hand, soak the lid parts in hot water for 30 minutes before cleaning them.
6. Use milk straight from the fridge, and check the froth knob is on MIN, MED or MAX froth.

Time: 5 minutes (quick clean), 40 minutes (deep clean by hand)
Cost: Free
Success Rate: About 20%
Difficulty: Easy

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Fix 4: Descale With the Milk Connection Accessory (Works About 15% of the Time)

Scale is on the Maestro's lists for blocked flow and for poor froth. The descale light turns orange when a cycle is due. The Maestro's procedure differs from the other La Specialista models: it has its own Descaling button and an accessory that plugs into the milk connection. The cycle takes about 40 minutes.

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

1. Remove the water softener filter if one is fitted.
2. Pour the descaler into the tank up to level A (one 100 ml packet), then add water up to level B (1 liter). Refit the tank.
3. Fit the descaling accessory to the LatteCrema connection.
4. Take the portafilter off. Put one container under the coffee outlet and hot water spout, and another under the steam wand.
5. Hold the Descaling button until its light blinks. Descaler runs through in a series of rinses and pauses until the tank is empty, then the light turns white.
6. Empty the containers, rinse the tank and fill it with fresh water to MAX.
7. Hold the Descaling button again until its light blinks to start the rinse.
8. Empty the containers and the drip tray, then refill the tank.

To descale before the light asks, hold the Descaling button for 3 seconds. To stop a cycle started by mistake, hold it for 10 seconds. 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 15%
Difficulty: Easy

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Fix 5: Use Active Rinse and the Outlet Cleaning Cycle (Works About 15% of the Time)

The Active Rinse button does two jobs. It rinses the coffee circuit, which the manual suggests for a blocked filter, and it runs the coffee outlet cleaning cycle. When its light comes on orange, the coffee outlet needs a full cleaning cycle with a coffee-machine cleaning tab. The tabs are sold separately, and the cleaning disk comes in the box.

1. Put the 1-cup filter in the portafilter, press the cleaning disk to its bottom and put a cleaning tab on the disk.
2. Attach the portafilter to the coffee outlet. Fill the tank and empty the drip tray.
3. Hold the Active Rinse button until its light blinks orange. The cycle stops by itself after a few minutes.
4. Remove the portafilter and disk. Wash the portafilter and filter under the tap.
5. Refit the portafilter and press Active Rinse to rinse, with a container underneath. Empty the drip tray.

Time: 10 minutes
Cost: A cleaning tab
Success Rate: About 15%
Difficulty: Easy

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When DIY Won't Work

Contact De'Longhi if:

• The triangle alarm light stays on. That's the general alarm.
• Espresso drips from the portafilter edges with it locked and a clean basket. The manual says to have the espresso boiler gasket replaced by Customer Services.
• The grinder won't grind after you've removed all the beans and cleaned the burr as the manual describes (selector anticlockwise to REMOVE, upper burr lifted out by its handle). See the Smart Tamping guide, Fix 5.
• The dose keeps falling even on the second grinding range. Worn burrs are replaced by a customer services center.
• You smell burning, the breaker trips, or water pools under the machine. Unplug it and stop using it.

Warranty: the manual warns against removing the exterior or cover and says attempting repairs voids the warranty. Repairs are for authorized service personnel only. Find a service center through delonghi.com.

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Keeping a Maestro Running

• Clean the LatteCrema System after every milk drink, then set the knob back to a froth position.
• Answer the orange lights: descale on the descale light, clean the coffee outlet on the Active Rinse light.
• Set the water hardness in the menu so the descale reminder matches your water.
• Brush the Smart Tamping Station and push the tube brush through the coffee funnel when the dose starts to drop.
• Run a rinse cycle before using it after more than a week off.

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FAQ

What does the triangle light mean on a La Specialista Maestro?

On its own and steady, it's the general alarm, and the manual's instruction is to contact Customer Services. Flashing together with the water light, it's a flow warning instead (Fix 1).

Does the Maestro have Sensor Grinding?

Its manual doesn't describe any. You set the dose with the coffee dose dial, which shows its level on the LED strip, until the tamped coffee reaches the mark in the filter. If the dial is at maximum and the dose is still short, the menu has a second grinding range.

How do I reset the Maestro to its default settings?

Hold X2 and My together for 5 seconds to open the menu, then hold OK for 5 seconds until the light stays fixed. Press ON/Standby to save. That restores settings, not a faulty machine.

Why is there no froth on my Maestro cappuccino?

The manual gives four causes: milk that isn't fridge-cold, the froth knob in the wrong position (often left on Clean), a dirty LatteCrema System, or scale. Fixes 3 and 4 cover them.

Does the Maestro need a special descaling step?

Yes. Unlike the Arte and Prestigio, it has a Descaling button, and its descaling accessory has to be fitted to the LatteCrema connection before you start (Fix 4).

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Related De'Longhi Guides

• La Specialista warning lights, all five models
• La Specialista Smart Tamping not working
• La Specialista leaking water
• La Specialista Prestigio not working
• La Specialista Arte not working
• De'Longhi grinder cleaning and maintenance

Sources: De'Longhi EC96XY (La Specialista Maestro) Instructions for use, US/Canada edition.