Proven: How To Get Urine Out Of Espresso Machine (2026)

By Elena Rodriguez · December 10, 2025

Immediate Action (First 5 Minutes)

I've been repairing and maintaining commercial and home espresso machines for over a decade. When a client called me in a panic because their toddler thought the Breville Dual Boiler's water tank was a toilet, I had to develop a rigorous sanitization protocol. Urine isn't just a stain. It is a corrosive biohazard that destroys ABS plastics and leaves behind uric acid crystals that survive standard washing.

If you are reading this, you are probably dealing with a similar nightmare involving a pet, a child, or a truly unfortunate prank. Don't panic. Unplug the machine right now. I mean it. Water and electricity don't mix, and you are dealing with a conductive biohazard that can easily short out your machine's main control board.

Next, pull the water tank straight up and out. Dump it in the toilet or a utility sink. Do not use your kitchen food prep sink if you can avoid it. Remove the drip tray, the metal grill, and the portafilter. If the urine pooled on the counter and seeped under the machine, grab a dry microfiber towel and soak up the perimeter moisture immediately. You have about five minutes before liquid wicks into the internal electronics or the pump housing.

Check the magnetic float valve inside the empty reservoir tank. This little plastic ring tells the machine it has water. Urine leaves behind sticky uric acid crystals that will jam this float, causing your machine to throw a 'Fill Tank' error even when it is full. Rinse it under warm tap water right now to keep the magnet moving freely.

What You'll Need (Tools & Products)

You can't just use soap and water here. Uric acid is notoriously stubborn and requires specific chemical breakdowns. I've tested dozens of cleaners on commercial espresso machines over my career, and standard kitchen sprays simply mask the odor while leaving the corrosive salts behind. This isn't the cheapest cleaning route, but replacing a $700 Gaggia Classic Pro is much worse.

Enzymatic Urine Destroyer: Nature's Miracle or Rocco & Roxie ($15-$22). You need real enzymes, not just scented surfactants.
Food-Grade Acid Sanitizer: Star San ($15 for 32oz). This is what brewers use to kill bacteria without leaving toxic residues.
Powdered Descaler: Urnex Dezcal ($18 for 4 packets). Essential for stripping uric acid off internal heating elements.
Detailing Brushes: A soft-bristle toothbrush and a 5.5mm Allen key for the shower screen.
Microfiber Cloths: A dedicated pack of 6 ($12) that you will throw away afterward.
Replacement Charcoal Water Filters: Specific to your brand ($20). Never reuse a filter exposed to biohazards.

Cleaner Type	Best Used For	Why It Works
Enzymatic Cleaner	Plastic Reservoirs & Drip Trays	Eats the uric acid crystals that cause lingering ammonia smells.
Acid Descaler	Internal Boilers & Thermoblocks	Strips mineral and biological scale off high-heat metal elements.
Star San (Acid Sanitizer)	Final Internal Flush	Kills remaining bacteria on contact and breaks down into harmless compounds.

Step-by-Step Removal

I'll be honest, this takes elbow grease and about 45 minutes of your morning. But if you follow these exact steps, your machine will be completely safe to use again.

Step 1: The Enzymatic Reservoir Soak (15 Minutes)

Take the removed water tank to your bathtub or utility sink. Spray the entire interior, especially the corners and the spring-valve at the bottom, with your enzymatic cleaner. Let it sit for exactly 15 minutes. Enzymes need time to literally digest the uric acid proteins. Do not rinse it yet. After 15 minutes, scrub the walls with a soft sponge, rinse with warm water, and let it air dry completely. If the tank has a charcoal filter holder, pull the old filter out and throw it in the trash.

Step 2: Dismantling and Scrubbing the Drip Area

Pull out the drip tray and remove the metal grate. If you have a Breville or Sage machine, there is often a secondary plastic trough hidden beneath the tray that catches overflow. Urine loves to pool here and crystallize. Soak the plastic tray in a basin of warm water and enzymatic cleaner. Use your toothbrush to scrub the metal grate, paying close attention to the welded seams where biological matter hides. Wipe down the empty cavity inside the machine base with a damp microfiber cloth sprayed with Star San.

Step 3: Flushing the Internal Boiler (The Scary Part)

If your machine was turned on and pulled urine into the internal pipes, the heating element is now coated in baked-on biohazard. You must strip this. Dissolve one packet of Urnex Dezcal in 32oz of warm distilled water. Pour this into your freshly cleaned reservoir. Place a large bowl under the group head and the steam wand. Run the brew cycle for 10 seconds, then stop. Let the descaler sit inside the boiler for 10 minutes to break down the uric acid scale. Repeat this process until the reservoir is empty. This isn't optional if the liquid breached the internal valve.

Step 4: Sanitizing the Group Head and Shower Screen

Grab your 5.5mm Allen key or a flathead screwdriver, depending on your model, and remove the single screw holding the shower screen in place. Drop the metal screen and the brass dispersion block into a cup of hot water mixed with Cafiza espresso detergent. Use your toothbrush to scrub the exposed silicone gasket inside the group head. Urine splashes back during brewing, and that gasket will harbor bacteria if you don't manually clean it. Rinse the parts, reassemble them, and tighten the screw firmly.

Step 5: The Steam Wand Purge

If the steam wand was resting in a puddle on the drip tray, capillary action might have drawn moisture up into the tip. Unscrew the steam wand nozzle. Soak the metal tip in hot soapy water for 5 minutes. Wipe the exterior of the wand with a Star San soaked cloth. Reattach the tip and purge the wand with high-pressure steam for a full 45 seconds to blow out any microscopic contaminants.

Step 6: The Final Purge and Filter Swap

Fill the clean reservoir with fresh, cold distilled water. Insert a brand new charcoal water filter. Run the entire tank through the brew cycle and the steam wand into a waste bowl. You need to flush out the descaler and any remaining sanitizer. Taste the water from the final pull. It should taste completely neutral. If you detect even a hint of ammonia or metallic tang, run one more tank of fresh water through the system.

Alternative Methods

Sometimes you don't have professional espresso chemicals on hand, or you're dealing with secondary damage like plastic staining. Here are two backup methods I use when I'm in a pinch.

Hydrogen Peroxide for Plastic Discoloration

Urine can cause a yellowish stain on the ABS plastic of your water reservoir or drip tray, especially if it sat for a few days. Standard soap won't lift this. Pour 3% hydrogen peroxide directly onto the stained plastic and let it sit in direct sunlight for 30 minutes. The UV light activates the peroxide, bleaching the uric acid stain out of the porous plastic. Rinse thoroughly afterward. This won't work on painted metals, but it works miracles on clear or black plastics.

Baking Soda Paste for Dried Crust on Stainless Steel

If the urine dried onto the stainless steel drip tray or the machine's exterior housing, it forms a hard, white crust that resists wiping. Mix three parts baking soda with one part Dawn dish soap to create a thick paste. Apply it to the crust and let it sit for 10 minutes. The alkaline nature of the baking soda neutralizes the acidic urine salts, while the soap lifts the oils. Scrub gently with a non-scratch sponge. I use this on my own Gaggia when my cat walks across the counter and leaves muddy, biological paw prints everywhere.

Prevention Tips

Once you've spent an hour deep-cleaning your machine, you'll want to ensure this never happens again. I've learned a few hard lessons about kitchen biology over the years.

Install an Acrylic Barrier: If you have cats that jump on the counter, buy a cheap acrylic splash guard from a hardware store and place it behind the machine. Cats hate the smooth, slippery surface and will avoid walking behind it to access the reservoir.
Use Citrus Deterrents: Felines despise the smell of citrus. Spray a lemon-orange essential oil mixture on the counter space surrounding your espresso machine. Do not spray it directly on the machine, as the oils can degrade the silicone seals over time.
Keep the Reservoir Lid Closed: It sounds obvious, but many people leave the plastic lid off the water tank for easy refilling. Keep it snapped shut. Most lids have a small flap that opens just enough for a pitcher spout, which blocks pets and toddlers from accessing the water.
Elevate the Machine: If you have a toddler who is fascinated by the shiny buttons and drip tray, consider placing the machine on a raised, heavy-duty stand that requires a step stool to reach. Out of sight usually means out of mind for a two-year-old.

FAQ

Can I save my machine if urine entered the internal boiler?

Yes, but it requires an aggressive chemical flush to strip the uric acid off the heating element. You'll need to run a heavy-duty descaler like Urnex Dezcal through the brew cycle at least three separate times. If the ammonia smell persists after 48 hours of drying, the internal silicone tubing might be permanently compromised and require professional replacement.

Will my coffee taste like ammonia after cleaning?

It shouldn't, provided you replaced the charcoal water filter and ran a minimum of three full reservoirs of fresh distilled water through the system. The enzymes break down the odor-causing bacteria, while the food-grade sanitizer neutralizes any lingering biological remnants. Always pull a few test shots and taste them before serving anything to your guests.

How do I clean the steam wand if it was resting in the puddle?

You must unscrew the steam wand tip and soak the metal tube in a cup of hot water mixed with espresso machine detergent like Cafiza. Never use enzymatic cleaners inside the steam wand, as the milk proteins and enzymes will clog the microscopic steam holes. Purge the wand with high-pressure steam for a full 30 seconds before reattaching the tip.

Is it safe to use bleach on the water reservoir?

Absolutely not, as bleach will permanently ruin the ABS plastic and leave toxic residues that are impossible to flush out of the internal valves. Bleach also reacts with the ammonia in urine to create dangerous chloramine gas, which is a severe respiratory hazard. Stick strictly to enzymatic cleaners and food-grade acid sanitizers for your own safety.