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A coffee maker leaking from the bottom is terrible news, regardless of where the leak comes from. This guide will help you understand what’s causing it, and how you can stop the leak. Any appliance that uses water to function is bound to spring a leak at least once in its lifetime. You can probably fix the leak without always replacing the appliance!
When your coffee maker leaks from the bottom, it’s likely because of a blocked drain, a leaking hose or a leaking hose connector. Water tank issues like cracks or faulty valves can also cause water to leak from your coffee maker, specifically at its bottom.
Why Is My Coffee Maker Leaking From Bottom?
Coffee machines deal with a lot of water, but that water is always contained within. So, any sign of water leaking from the bottom of your machine signifies a problem.
Here are the most likely problems causing that leak and what you can do to solve them:
1. Blocked Drain
About this part: One of the many components of your coffee machine is its drip tray. The name is a very strong hint as to its purpose: it catches all the dripping liquids that result from your coffee brewing.
Some drip trays are to be emptied manually, like most household coffee makers. However, others are plumbed. That means the drip tray has a permanent hose that drains all fluid directly into your household plumbing.
How it happens: The first reason your coffee maker leaks from the bottom is a blockage in its drain. But, of course, this only applies to drip trays that are meant to drain automatically.
You’ll know that the leaking water comes from the drain if it’s brown or otherwise dirty. That’s because the water has already gone through the brewing process and is no longer clean.
The blockage is most likely caused by coffee grounds stuck inside the hose. But, of course, other impurities and dirt can also add to the problem and worsen it.
When that happens, water from the drip tray fails to drain through the hose. It will then accumulate and leak out from any available opening underneath the coffee maker.
How to fix it: You can solve this problem by removing the blockage in your coffee maker’s drain. That includes removing the hose and flushing it from both ends to loosen and remove the clog.
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Read: How To Clean A Breville Coffee Machine? Step By Step Guide
2. Leaking Hose Or Hose Connector
About this part: Coffee makers have several hoses or tubes inside the main unit. These are necessary to transport water from where it’s stored straight through to where it’s boiled to brew your coffee.
The hose inside isn’t a long, singular piece. Instead, it’s a series of hoses linked together with connectors to direct water flow as needed.
How it happens: The second cause a coffee machine leaks from the bottom is because of a leak in the hoses or hose connectors.
There’s a strong chance that a hose inside your coffee machine disconnected from a hose connector. As a result, water from the hose flows towards the machine’s bottom.
Although less likely, it’s also possible that a pinhole leak developed in one of the hoses. That, too, will cause water to leak from the bottom of your coffee maker.
Remember: coffee machine hoses are typically divided into multiple sections. That’s excellent news for this repair because it means you’ll only have to replace the affected section (and not the entire hose).
So, open your coffee machine’s panel and locate the leaking hose. Then, remove it and install a new replacement hose in its place.
Read: Why Breville Coffee Machine Not Turning On? – Troubleshooting Guide
3. Worn-Out Water Tank Valve
About this part: Many household coffee machines aren’t plumbed. So instead of a water intake, they rely on a reservoir or tank to store water. The coffee maker will draw water from that tank whenever it needs to brew coffee.
Water tanks and reservoirs have a valve at the bottom that controls the water flow. The valve keeps water inside the tank and ensures it only flows out when necessary.
How it happens: Water can leak from the bottom of your coffee maker if the water tank valve is worn-out. The chances of that being the root cause are higher on coffee makers that have been in use for many years.
A worn-out valve fails to keep water stored inside the water tank. Instead, it’ll cause water to drip or flow slowly towards the underside of the coffee maker.
You’ll know the water is coming from the tank if it’s clear, as it hasn’t been used for coffee brewing.
How to fix it: Worn-out water tank valves are replaceable. First, empty the water tank or reservoir. That’ll allow you to replace the existing valve with a new one.
Be sure to test the valve before you put the water tank back in your coffee maker.
Read: 4 Common Ninja Coffee Maker Problems
4. Cracked Water Tank
About this part: Aside from a worn-out water tank valve, you must also consider that the tank itself is cracked.
The water tanks you find in coffee makers are typically made from durable plastic. But, despite that, they’re not indestructible.
External impacts like that from dropping the water tank in your sink can cause small cracks to develop.
All it takes is a tiny crack for water to drip out from the water tank and collect underneath the machine.
How it happens: As mentioned before, you’ll know the water is coming from the tank if it’s clear, as it hasn’t been used for coffee brewing.
The crack on the water tank can form after you drop it or hit it with something hard.
How to fix it: Ideally, you should replace your cracked water tank with a new one. However, that might take some time, so you can patch the crack with silicone or use a strong tape as a short-term solution.
Remember: that should only be used as a short-term solution. Replacing the tank with a new one can be pretty pricey, depending on your coffee maker’s brand and model.
However, it’s a worthwhile purchase, especially if you rely heavily on that machine daily.
Read: Cuisinart Coffee Maker Troubleshooting
Frequently Asked Questions (FAQs)
Here are a few more helpful questions about coffee maker leaks:
Can Coffee Machines Grow Mold?
Yes, coffee machines can grow mold if they’re not used and cleaned regularly. In addition, leaks can worsen the mould problem by allowing water to reach places it doesn’t belong. And wherever there’s water, there will be mold growth.
What Do I Do If Water Is Leaking From The Espresso Machine?
When water leaks from your espresso machine, shut it off immediately. You must identify the source of the leak and resolve it immediately. Don’t delay fixing it, as that could lead to much bigger problems that cost more to fix.
Read: 4 Common Keurig Coffee Maker Issues
Can You Seal A Cracked Coffee Machine Water Tank?
Yes, you can temporarily seal a cracked coffee machine water tank with silicone. However, this should only be a temporary solution. You’ll want to get a new water tank before the problem worsens.
What Can I Use To Patch A Plastic Water Tank?
You can use waterproof tape to temporarily patch the leaking tank on your coffee machine. That will prevent or slow the water leak while you find a replacement tank.
What Is The Difference Between A Seal And A Gasket?
A gasket is a static seal between two parts of your coffee machine. However, a seal is typically used to prevent leaks in moving parts. These two terms are interchangeable, so different coffee machine manufacturers might use either in their user manuals.
