hi, my Cimbali M32 Dosatron hightop keeps overfilling and does not heat up, any ideas or advice would be appreciated and is it possible to obtain a repair/fault finding manual for this machine. Rgds

Most likely the boiler probe has scale build-up. The machine will not heat up until it is satisfied that the boiler is full.

More details would help. Does the machine act normally other than that? Do the lights and LCD come on, etc.??

There are parts diagrams, but I don't know about repair manuals.

hi cyclone, thanks for reply.
The machine starts to operate normaly when switched on, but when pump cuts out after filling boiler a few minutes later the boiler starts to overflow and does not heat up. Rgds Robby

I think Chris' diagnosis is right. To elaborate, your espresso machine is a heat exchanger design, i.e., the boiler is kept partially filled to allow for a layer of steam. Since the water is under pressure, its boiling point is higher, just like in an old-fashioned pressure cooker. If the water level probe is covered in scale, it fails to detect ground and the controller calls for water. No room for steam => no steam pressure => water heats up, expands, and overflows boiler through the vacuum breaker. Because the pressurestat reading is bogus, the boiler does not heat to the correct operating temperature.

I recommend you engage a qualified service repairman to assess the boiler level problem and also address the root cause, scale buildup. Below is an example of severe scale:


From Rancilio Z9 Two Group Lever Machine

Bought my M31 Dosatron in 1998 never had any major problems with this machine. Just recently pulled out my heating elements to check them, got carried away and opened the boiler, very small amounts of lime back and front. After cleaning the elements back to the original copper and a spotless drum the water heating is now silent. Just like your car they need a service, from time to time...i enjoy doing it myself.