The original pump in your machine may have been the EX5 or EP5, and we are now supplying the EAP5. All three of these pump versions are interchangeable and produce the same 15 bar pressure.
The lifespan of these pumps varies greatly, usually anywhere between 5 and 15 years, and primarily depends on what model of machine they’re installed in and how the machine is used. Some machines use a rapid pulsing of the pump during extraction to improve the flavor of the coffee, and others run the pump continuously for several minutes during the descaling cycle. Both of these behaviors can cause the pump to overheat and have a diminished service life, particularly the descaling. If your machine is one of those that seems to run the pump forever during descaling, we recommend using the “pause” function (if available) after every 2 minutes of continuous operation, waiting 2 minutes for the pump to cool, and repeating until complete. This should greatly improve your pump’s service life.
There are a few different failure modes for these pumps, so if your machine won’t make coffee don’t assume it’s not a bad pump just because the pump makes noise or you can run the steam function. These pumps have a diode molded into the casing, which can either fail open (pump will be silent), or can short out (pump will emit a weak 60 Hz electrical buzz, and eventually the diode will burn up and fail open). A shorted out diode will still allow the pump to move a small amount of water, but with negligible pressure. You may be able to get some intermittent spurting or droplets through the steam wand, but will not be able to make coffee. The pump also has check valves inside, which can wear out or stick. If your machine has been sitting for a long time and now won’t pump water, the valves may just be stuck and you can get your machine working again by applying pressure to the water intake with a priming tool or industrial syringe.
If you think your pump may be failing, under no circumstances should you attempt to descale it, unless you are within driving distance of a repair shop. More than likely, the pump will fail completely while the system is full of descaling chemical, and if you ship it in that condition that chemical will inevitably find its way out of the water circuit and end up all over the inside and outside of the machine, and cause corrosion of any exposed electrical components. Descaling is a preventative action, and almost never fixes an already existing problem.
Espresso Resource NW
5305 NE 121st Ave
Vancouver, WA 98682