Jura S8 Problems & Error Codes? Complete Fix Guide

Reading an S8 Touchscreen Message

On the Jura S8, problems show as touchscreen messages: Fill water tank, Empty coffee grounds container, Decalcify machine and so on. Each has one documented answer. Numbered errors are rare. The manual defines Error 2 and Error 5 (too cold, so heating is disabled: warm the machine to room temperature) and says to switch off and call JURA for any other.

The S8 has one row its siblings don't: Fill water tank shows even though the tank is full. The cause is a trapped float in the tank, and the fix is to descale the tank. It isn't a sensor to replace.

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Try This First

• Touch the message. Maintenance prompts (Clean machine, Decalcify machine, Change the filter) start their program from the message itself.
• Empty the grounds container with the S8 switched on. That resets the grounds counter. Emptying it with the machine off doesn't.
• Push the drip tray fully in.
• Warm it up. If it's been in a cold car, garage or shipment, Error 2 or 5 clears at room temperature.

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S8 Display Messages

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Fix 1: Clear the Blocking Messages (Works About 35% of the Time)

Fill water tank, Empty coffee grounds container and Drip tray not fitted each stop every drink.

1. Fill the 64 oz (1.9 l) tank with fresh, cold water and seat it.
2. With the S8 on, empty the grounds container (up to 16 portions) and the drip tray, rinse them and put them back.
3. Make sure the drip tray is fully inserted.
4. Change the tank water daily.

Time: 2 minutes
Cost: Free
Success Rate: About 35%
Difficulty: Easy

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Fix 2: "Fill Water Tank" With a Full Tank: Free the Float (Works About 15% of the Time)

The S8 detects water with a float in the tank. Limescale can stop it moving. The manual's fix is to descale the tank.

1. Remove the tank and take out the CLEARYL Smart filter if one is fitted.
2. Fill the tank and dissolve 3 JURA descaling tablets in it.
3. Leave it for several hours (overnight is fine).
4. Empty it, rinse it thoroughly, refit the filter and refill with fresh water.

Time: Overnight (5 minutes hands-on)
Cost: 3 JURA descaling tablets
Success Rate: About 15%
Difficulty: Easy

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Fix 3: Run Clean, Decalcify and Filter Changes (Works About 25% of the Time)

The S8 asks for each maintenance job when it's due. A CLEARYL Smart filter in the tank means it won't ask for descaling.

1. Clean machine: about 20 minutes with one JURA cleaning tablet. Due after 180 preparations or 80 switch-on rinses.
2. Decalcify machine: touch the message, then Descale, then Start twice. Use 3 JURA descaling tablets in 17 oz (500 ml) of water. Allow about 45 minutes, and don't interrupt it. Full descaling steps.
3. Change the filter: fit a new CLEARYL Smart cartridge.
4. Machine too hot for maintenance: wait several minutes, or make a coffee or hot water, then start.

Time: 20-45 minutes
Cost: JURA tablets or a filter
Success Rate: About 25%
Difficulty: Easy

JURA warns that other descaling agents, vinegar included, "could damage the machine or leave residues".

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Fix 4: Coffee Drips or Tastes Weak (Works About 15% of the Time)

The S8's dripping-coffee row has two causes: grounds too fine, blocking the system, and a water hardness setting that's wrong, so scale built up unprompted.

1. Set the grinder adjustment switch coarser. Change it only while the grinder is running, as JURA's grinder instructions say.
2. Check the water hardness setting with the supplied test strip.
3. Run the descaling program.
4. Dry grounds behind the grounds container means the beans give above-average grounds. Lower the coffee strength (10 levels per product) or grind finer.

Time: 5-45 minutes
Cost: Free
Success Rate: About 15%
Difficulty: Easy

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Fix 5: Milk Foam, Loud Grinder and Errors (Works About 10% of the Time)

1. Poor foam or milk spraying from the professional fine foam frother: clean it with JURA milk system cleaner, then dismantle and rinse it.
2. Little or no water or steam from the frother, pump very quiet: unscrew the black connector with the hexagonal hole in the measuring spoon, clean it and refit it by hand.
3. Grinder very loud: foreign objects in the grinder. Contact JURA.
4. Error 2 / Error 5: warm to room temperature.
5. Any other Error: switch the S8 off with the On/Off button and contact JURA.

Time: 5-15 minutes
Cost: JURA milk system cleaner
Success Rate: About 10%
Difficulty: Easy

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S8 Settings That Change the Cup

Per product, the S8 stores a coffee strength (10 levels), an amount (espresso 0.5-2.5 oz, coffee 0.5-8 oz) and a temperature: low, normal or high. If the coffee runs cool, set the product's temperature to high and prewarm the cup. JURA says "the full coffee aroma can develop only in prewarmed cups".

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When to Call JURA

• Any Error other than 2 or 5
• A very loud grinder
• A burning smell or damage: unplug immediately
• Water under the machine. The S8 manual has no owner leak repair, and "NO user serviceable parts" sit behind the covers.

JURA USA: 1-800-220-5701 · Canada: 1-855-544-8600.

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FAQ

Why does my Jura S8 say Fill water tank when it's full?

The manual's cause is a trapped float in the water tank. Descale the tank: 3 JURA descaling tablets in a full tank, left for several hours, then rinse it thoroughly.

How long does an S8 descale take?

About 45 minutes. It starts from the Decalcify machine message and needs 3 JURA tablets dissolved in 17 oz (500 ml) of water. Don't interrupt it once it's running.

Can I reset an error on the S8?

Only Error 2 and Error 5 have a home fix: let the machine warm up to room temperature. For any other Error, JURA says to switch off and contact customer support.

Can I make S8 coffee hotter?

Yes. Each product has a temperature setting of low, normal or high in its product settings. Prewarming the cup also helps.

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Related Jura Guides

• Jura Troubleshooting Guide: all models
• Jura Descaling Guide: step by step
• Jura Z6 Problems: the Rotary Switch models
• Jura Not Heating?: lukewarm coffee

Sources: JURA S8 Instructions for Use (J73481/S8/US-en/202105).