A leaking espresso machine it not fun nor safe so fixing it both quickly and correctly is incredibly important. However, before you can fix a leaking expresso machine you first need to work out why the machine is leaking in the first place.
Based on my many years of owning an espresso machine these are the reasons as to why I’ve found espresso machines leak.
1. Crack In The Water tank
If your water tank is made from plastic, there is a chance with time and use that it may start to crack without you noticing. Check for any hairline marks around the sides and bottom.
If you can’t see anything obvious, fill the tank and leave it sitting in an empty basin for a while to see if any water leaks out. If it turns out there is a crack, buying a new water tank for your machine should be pretty easy but this does depend on the model of your espresso machine.
2. Seals Are Worn Out
To keep your espresso machine working efficiently and to streamline the water correctly through to the coffee, most models will have a number of different rubber seals in place throughout the machine. These rubber seals never last forever and with use, there will start to get worn out.
If you are experiencing a leak, check the different seals throughout your machine for any signs of them not working or becoming thin and worn out. Again, these should be easy to replace from certain suppliers or direct through the manufacturer of your specific machine.
3. Burst Pipe
Within your machine, the water will travel from the water tank to the percolator via pipes, tubes or other channels.
If these pipes are easy to access, it may be worth checking to see if the pipes themselves are leak-free or if there are signs of damage or dampness around the outside of the pipes.
It if appears that the pipe is the source of the leak it will be best to contact the customer support service of your machine supplier for advice.
4. The Portafilter Is No Longer Watertight
The portafilter is the removable handle that contains the coffee grounds that is then attached to the machine to allowed the water to drip through it.
Because it is often the main part of the machine that is constantly being removed and attached, the gasket or seal may start to wear. This leak will be more noticeable as the water will start to leak out on the sides of the portafilter rather than running through the coffee.
This is potentially an easy fix as a new gasket can be bought and replaced. Do also check that the portafilter itself isn’t damaged or dented. Because it is a removable part of the machine it is likely to get more wear and tear marks. Minor damage of the portafilter could also lead to leaks.
5. Steam Nozzle Is Scaled
With continued use, the steam nozzle on your espresso machine can build up limescale, much like a kettle. Though this may not directly cause a leak, the blocking of water in the steam nozzle may encourage the water to seep out elsewhere within the machine.
The limescale can be removed by soaking the steam nozzle in a simple hot water, lemon or vinegar solution or a store-bought limescale remover.
To make sure the steam nozzle stays clear of limescale, simply clean it after every use with a damp cloth and then deep clean it regularly with your chosen limescale remover solution.
6. Position Valve Is Loose
Within the machine, there is a position valve that directs the water from the tank either to the coffee percolator or to the steam nozzle depending on what setting you select.
Because this is a point in the system where pipes join, there is a higher risk for water to leak through loose connections. Depending on your machine, the position valve may be hard to access so it is best to contact your machine’s customer support service if you do think there is a leak coming from the position valve.
7. Blocked Drainage
This is only a concern if your machine has its own drainage system into your greywater tank. If there is a blockage somewhere it could cause the greywater to leak.
If your machine is leaking and the water looks dirty, that could be a sign that its greywater that is leaking rather than the freshwater running through the machine.
Check with the manufacturer of your machine, but it should be easy enough to solve the blockage with drainage solution like you would use to unblock your sink.
8. Overfilling the Water Tank
It seems like an obvious and simple one, but quite often the max level sign on the water tank isn’t always clear or it can sometimes feel like its easier just to fill the tank all the way to the top to save from you constantly refilling it.
Similar to overfilling a kettle, when water starts to heat, the water is likely to boil over and leak out of the top of the water tank. If you think this might be happening when you using your machine, fill the tank only half full and see if that makes a difference.
If that helps, you can then figure out exactly how much water your machine can take without it boiling over and leaking.
9. Wrong Parts
It can be tempting to buy cheaper options when replacing parts of your espresso machine but this may be more hassle than its worth. More often than not different machines and models have unique pieces and so ‘universal’ seals, gaskets, valves just may not be quite the right fit and thus may be the cause of potential leaks.
The best way to maintain your machine is to buy parts either directly from the manufacturer of your machine or from companies that the manufacturer approves and rates as suitable suppliers for parts. This will ensure that your machine functions optimally and that malfunctions and the possibility of leaks are minimised.