The removable brew group should be rinsed once a week to prevent coffee residue building up around the brewing chamber and moving parts.

1. Switch the machine off using the power button and wait until it has completely stopped operating.
   
2. Remove the water tank to give yourself clear access to the service door.
   
3. Open the service door on the side of the machine.
   
4. Press the PUSH button on the brew group while pulling the brew group towards you.
   
5. Rinse the complete brew group thoroughly under lukewarm running water.
   
6. Pay particular attention to the filter/screen and areas where compacted coffee grounds collect.
   
7. Do not use washing-up liquid or other household cleaning products on the brew group.
   
8. Shake off excess water and leave the brew group to air-dry.
   
9. Before refitting it, check that the brew group is in its neutral/rest position.
   
10. Slide it back along the internal guides until it locks into position. Do not press the PUSH button while inserting it.
    
11. Close the service door and refit the water tank.
    
12. Switch the machine back on and allow it to complete its normal start-up cycle.
    

If the brew group becomes difficult to operate or starts making more mechanical noise than usual, it may also need lubrication. The 4300 uses a removable, serviceable brew group specifically designed for regular cleaning.

The 4300 LatteGo system uses a two-part milk container with no internal milk tubes, making it straightforward to dismantle completely for cleaning.

1. Remove the LatteGo container from the machine after preparing milk drinks.
   
2. If milk remains, store it appropriately rather than leaving the filled container attached to the machine for long periods.
   
3. Separate the milk container from the LatteGo frame.
   
4. Rinse both parts under clean running water, making sure no milk residue remains around the connection and milk outlet areas.
   
5. Pay particular attention to dried milk around the channel where milk and air are mixed, as contamination here can affect frothing.
   
6. For a more thorough clean, wash the components with warm water or place the suitable LatteGo parts in the dishwasher.
   
7. Allow the parts to drain before reassembling them.
   
8. Reconnect the milk container and frame correctly so that the two sections sit firmly together.
   
9. Refit LatteGo to the machine and make sure it is fully seated before selecting a milk drink.
   

If milk foam suddenly becomes poor, clean the LatteGo thoroughly before changing machine settings. Incorrect assembly, dried milk residue and milk temperature can all affect the result.

The LatteGo milk system and other specified removable components are dishwasher safe.

Preparing the AquaClean filter properly is important. Installing a filter containing trapped air can result in poor water flow, excessive pump noise or no coffee being dispensed.

1. Remove the water tank from the machine.
   
2. Remove the old AquaClean filter if one is already installed.
   
3. Take the new filter and shake it for approximately 5 seconds.
   
4. Fill a bowl or container with clean water.
   
5. Turn the filter upside down and immerse it in the water.
   
6. Keep it submerged until air bubbles stop escaping from the filter.
   
7. Push the prepared filter firmly into the filter connection inside the water tank.
   
8. Fill the tank with fresh water and refit it fully into the machine.
   
9. Follow the AquaClean activation instructions shown on the 4300 display.
   
10. Once the machine has heated, use the Hot Water function to establish a steady water supply if necessary.
    

If the machine becomes noisy or stops dispensing after a filter change, remove the filter temporarily and test the machine again. Dispensing 2–3 cups of hot water can help clear air from the circuit. If water flows normally without the filter, prepare the filter again or replace it if it has become restricted.

The 4300 has a guided descaling programme through its display, so use the machine's Clean menu rather than attempting to manually flush descaler through it. The complete programme takes approximately 30 minutes.

1. Touch the Clean icon on the display.
   
2. Select Descaling from the menu.
   
3. Follow the instructions displayed on the machine.
   
4. Remove the LatteGo milk container or milk frother if fitted.
   
5. Remove the drip tray and coffee grounds container.
   
6. Empty both and reinstall them.
   
7. Remove the water tank.
   
8. Remove the AquaClean filter from the tank.
   
9. Empty any remaining water from the tank.
   
10. Add the required descaling solution.
    
11. Add fresh water up to the Calc/Clean indication on the water tank.
    
12. Refit the water tank.
    
13. Place a container capable of holding at least 1.5 litres underneath the coffee dispensing spout and water spout.
    
14. Press the Start/Stop button to begin.
    
15. Allow the machine to run the programme without interrupting it. It will dispense the solution through the machine in stages.
    
16. When instructed on the display, remove and rinse the water tank.
    
17. Refill the tank with clean water.
    
18. Refit it and continue with the rinsing stage.
    
19. Wait until the machine finishes dispensing and confirms that the programme has completed.
    
20. Prepare, install and activate a new AquaClean filter if you use one.
    

Do not simply stop once the descaling solution has passed through the machine. The rinsing stage is part of the programme and needs to complete before making coffee again.