Fixing a Leak
Have you ever noticed steam or hot water leaking through the brew group on your home espresso machine? A little leaking as the boiler heats up to brew or steam temperature is normal. When water heats it expands which creates more pressure in the boiler. This pressure may allow some water to sneak by. If the leak becomes excessive or leaks constantly, you may be able to fix it yourself. The home machines we are going to discuss do not have the three-way valve, like higher end machines. In their place they have a spring-loaded rubber valve. Included are the following machines: all Francis Francis, all Saeco non super automatic machines, Solis SL90 and SL70, La Pavoni Duet, Pisa, Lusso and Espresso, Gaggia Espresso, Carezza, Coffee and Gran. Not included are the Gaggia Classic, Gaggia Baby and Rancilio Silvia because they have a three way solenoid valve.
This valve is located behind the shower screen and keeps the water from being forced out of the boiler as it heats and the water expands. When you want to make coffee and turn the pump on the valve will stay closed until enough pressure is built up to push it open allowing the water to flow. When you turn the pump off, the pressure reduces and the spring on the valve pushes it closed. When the steam button is pushed the boiler heats up to a higher temperature and the pressure in the boiler increases putting more strain on the valve. With some machines, even when new, you might get a little water or steam being released. It will usually happen in a little puff that lasts a second or two. Over time the rubber valve may become old, hard and disfigured or minerals from the water may start to build up on it. If this happens you will notice an increase in the amount of steam and or water being released through the brew group when the pump is off.
If you decide that it is time to make this leaking stop you may be able to fix it yourself. If the machine is still under warranty you may void the warranty any time you take it apart. If it is out of warranty and you want to try it yourself read on.
This rubber valve is located behind the shower screen, so, remove the screen first. It is held in place with one screw. Sometime this screw can be tight, and even though it is a stainless steel screw, the head on it can be stripped easily. So, before you attempt this make sure you have a short screwdriver that fits it perfectly. This may require two trips to the hardware store. Once you have the proper screwdriver try to remove the screw and if it does not come out we have to go to plan B. Lay the machine on its back with its top up against a wall. Use one hand on the very end of the screwdriver to hold it very firmly against the screw. With the other hand use a big pair of pliers or an equivalent tool to grab onto the screwdriver to turn it. Remember to remove the screw turn it counter-clockwise. If the shower screen does not fall out you may have to use a small screwdriver to pry it out, using the hole where the screw was. You will now notice a small contraption in the center where the water comes out. This is the valve that you have to remove and clean. If you have a Gaggia machine you will have to remove the two Allen screws under the shower screen and pry out the disc which is called a “shower holding plate” to access the spring loaded valve (Please see below for more information on Gaggia). Please keep in mind that each machine is a little different. At this point look up at the valve and see what tool you will need to remove it. With most machines a flat head screwdriver will do the trick. Pay close attention to how it comes apart so that you can make sure you put it back together properly. Once you have it out you can clean it thoroughly. Also look up into and clean out the inside of the hole that it came out of. Make sure the area that the rubber valve seats up against is also very clean. Now put it back together and try it out. If it still does not seal you may want to replace the rubber valve and spring. It is possible that you can extend the spring a little to put a little more pressure on the rubber valve. For more information or parts please call the manufacturer. For Gaggia call us.
One-way to avoid having this problem in the first place is to decalcify your espresso machine every two or three months. Look for more information on this in future newsletters or send me an email for more info.