Troubleshoot steam boiler heating issues on the Bezzera DUO DE by following the steps below.
Steam Not Heating
- If the machine is producing steam, but you think it's not producing enough steam, make sure that you are purging the line before frothing. To purge the line simply open the steam knob and let steam come through until it changes from mostly water to mostly steam. When steam leaves the boiler and hits the cold wand it is going to condense back into water. If you do not purge the line it will affect the way the steam wand froths.
- Make sure the steam boiler is turned on for the machine. Most prosumer units feature a switch, button, or PID menu option to turn the steam boiler off.
- Give the machine sufficient time to heat up. A heating time of 20-30 minutes is recommended for prosumer style machines for it to be sufficiently heated for brewing. Make sure the portafilter is attached during heating.
- Make sure the heating indicator is on. If the heating indicator is not on, then the machine will not heat. Typically this light will be off if the machine is out of water or not able to fill the boiler.
- The pressurestat may be set too low resulting in a lower brew temperature. Be cautious when adjusting the pressurestat. Setting it too high can cause the machine to overheat, resulting in the pressure relief valve blowing off excess steam.
- Unplug the machine and remove the machine case.
- Once the case is removed, locate the Mater pressurestat, which will be located behind the boiler on the left hand side of the machine.
- The adjustment screw for the pressurestat is located on the top. To adjust the pressure, turn the screw a quarter of a turn at a time; a small adjustment will make a large change in steam pressure and brew temperature. Clockwise will raise the pressure, counter-clockwise will lower it. Bear in mind that on this machine the steam pressure and brew temperature are correlated, and one can't be changed without affecting the other.
- The high limit switch may be tripped and needs to be reset. Instructions for resetting the high limit switch can be found in the attachment below.
- The heating element may be broken and may require replacement.