KB90 Cleaning and Operating Guide
- Isabella Runge (Unlicensed)
La Marzocco KB90 Coffee Machine
Steam Boiler - 1.3-1.5 bar - 11 litres
Coffee Boiler - 9 bar - 3 x 1.3 litres
Parts Diagram
Main Switch
Pressure Gauge (Steam & Brew water)
Brew Groups
Control Panel
Group #1 Keypad
Digital Display
Steam Wand
Steam Knob
Hot Water dispense nozzle
Removable Drain Tray
Hot Water Button
Cup Warmer Button
Hot Water Mix Valve
Straight-in
Precision Scale
Operations
Straight-in
 Push into portafilter support. |  Pull up to lock handle in. |  Press desired button. |
 Press down on button. |  Push handle down. |  Pull out of portafilter support. |
Programming Keypad
Button 1 - T1
Button 2 - T2
Button 3 - T3
Cleaning
Cleaning Cycles
To enable the washing procedure, press and hold at the same time the buttons T1 and T3. This activates the washing procedure of each group.
When activated, the water pump comes into operation, and the electric valve of the specific group being washes will turn on and off the cycle. There are about 10 preset cycles with an interval of 4 seconds. To manually stop the rinsing, press any key.
Note: At the end of the day, add the required amount of coffee machine chemical into the blind portafilter basket and insert it in the group to be rinsed before activating the rinsing process.
Note: Rinsing multiple group heads simultaneously could cause the drain box to overflow.
WARNING: DO NOT PERFORM THE CLEANING PROCEDURE WHEN OTHER GROUP HEADS ARE DISPENSING COFFEE.
Cleaning Filters
Put 2 or 3 teaspoons of espresso machine cleaner in about 1/2 a litre of water inside a heat-resistant container and boil.
Dip filters in the boiled solution and leave them fully submerged for about 30 minutes.
Rinse thoroughly with clean water and run hot water through one group several times with the filters in place.
Make one cup of coffee and discard in order to remove any unpleasant flavor.
Cleaning Portafilters
Using the proper cleaning tool (green scourer) wash the filter holders under hot water with detergent.
Cleaning the Drip Tray
Remove the drip tray grill everyday to clean, pull out the water drain collector and clean it thoroughly. Wash in sink with warm water and detergent, using a green scourer. Inspect and clean also the drain box and remove any leftover grounds at least twice a week.
Cleaning the Steam Wand
The steam wand must be cleaned after every use with a damp cloth.
WARNING: DO NOT USE ABRASIVE MATERIALS ON THE COFFEE MACHINE
Troubleshooting
This espresso machine is equipped with several feedback mechanisms that alert the operator when an unusual condition occurs.
Additionally the espresso machine will warn the operator when certain parameters fall below or above the programmed point. These errors and warnings will appear as a message in the display.
The following section will describe errors and warnings that may appear in the display.
Message | Description | Message Solution |
|---|---|---|
| This message is displayed when the CPU does not detect a full signal from the steam boiler within the set time interval. | When this message is displayed the CPU also shuts down and turns off power to the machine (see the parameter “Level Timeout”). Press the ON/OFF button to reset this error. |
| This message is displayed when the CPU does not detect the temperature probe. | When this message is displayed the CPU shuts down and turns off the machine. The way to reset this error is to verify and to reconnect the temperature probe. |
| This message is displayed during first installation and when preset of settings is made. | Push enter if Steam Boiler is filled. Verify the presence of water looking the sight glass. |
| This message is displayed during first installation and when preset of settings is made. | Push enter if groups have been blend ie no air is present in groups. |
| This message is displayed when the coffee boiler does not reach the minimum temperature with the programmed time interval. | See the parameter “Heating Timeout” for more information. The number on the display corresponds to the number of the faulty coffee boiler. |
| This message is displayed when the coffee boiler temperature exceeds the maximum allowed temperature. | When this message is displayed call an authorized service technician to repair this fault. The also CPU turns power off to the coffee boiler. |
| This message is displayed when the CPU does not detect the temperature probe. | When this message is displayed the CPU shuts down and turns off the machine. The way to reset this error is to verify and to reconnect the temperature probe. |
| This message is displayed when the steam boiler temperature exceeds the maximum allowed temperature. | When this message is displayed call an authorized service technician to repair this fault. The also CPU turns power off to the steam boiler. |
| This message is displayed when the steam boiler does not reach the minimum temperature with the programmed time interval. | See the parameter “Heating Timeout” for more information. |
| This message is displayed when the temperature of the coffee boiler neck resistance increases by 5°C over one minute, despite it being switched off. | When this message is displayed immediately switch off the machine and contact an authorised maintenance technician to have the failure repaired. When this alarm is notified, the LEDs on the cup heater and hot water buttons blink. |
| This message is displayed when the steam boiler level probe has not detected the water level for at least 2 seconds. | When this message is displayed please contact an authorised maintenance technician to have the failure repaired. When this alarm is notified, the LEDs on the cup heater and hot water buttons blink. |
| This message is displayed when the temperature of the coffee boiler neck resistance increases by 5°C over one minute, despite it being switched off. | When this message is displayed immediately switch off the machine and contact an authorised maintenance technician to have the failure repaired. When this alarm is notified, the LEDs on the cup heater and hot water buttons blink. |
| This message is displayed when the CPU does not receive the appropriate signal from the flowmeter. | When the flowmeter alarm is displayed, push a button to turn off the alarm. This problem is a result of water not flowing through the flow meter. This can be caused by the coffee packed too tightly, a blockage in the tubes, a malfunctioning water pump, a faulty valve, or a damaged flowmeter. Call a service technician to ix this problem. |
| This message is displayed when the steam boiler autofill cycle is activated and water is entering the steam boiler. | No action is required when this message is displayed. This message is only displayed to notify the operator of the active process. |
| This message is displayed when password entered does not match the programmed password. | This error message will be displayed anytime an incorrect password is entered. The machine comes back to the previous state. |
| This message is displayed when the filter alarm is on. All the buttons flash | When this message is displayed perform the required maintenance operations on the water filter or replace it. |
Warnings
WARNING: PLEASE READ THE BELOW
Do not remove the portafilter while relative group is brewing hot liquids. This operation can be extremely dangerous since the high pressure built-up inside the blind filter would spray out hot and slightly caustic water, which may cause severe burns.
The Coffee Boiler contains water at elevated temperature. Water temperature over 52°C can cause severe burns instantly or death from scalding.
The individual grid of the coffee scale is a fragile component, handle and store with care. Handle with care maximum load 1kg do not lift. The height of the bottom tray is fixed.