In all probability you have a refrigeration problem, of which there are two main causes. Firstly, the compressor may be faulty, generally not running at all but sometimes appearing to run but not pumping correctly.
Secondly, the machine may have a leak in the system and has lost its gas. In this case, the compressor will be running but to no effect.
The other possible cause is that you have a fault on the electronics delay board meaning that there is no power getting to the compressor and therefore it does not run. To check this you need to connect the compressor directly to the mains power to test whether it is working. Not all machines have electronics delay boards but they are common on Ugolini, Sencotel, GBG and Slush Puppie machines.
There are a few possibilities when this occurs. By far the most common is that the condenser of the machine is blocked with a combination of dust, fluff and grease meaning that the fan is unable to draw sufficient air through to cool the refrigerant gas. Another possibility is that you have accidentally blocked the air flow by putting the machine too close to a wall or other equipment, or that something has been placed up against the machine. You need to check these possibilities and clear the blockage to allow the machine to function correctly.
You also need to check that the fan is running at its correct speed and drawing air into the machine effectively. If all is OK then you need to check that the slush has been diluted correctly. If there is too much syrup in the diluted slush then the machine will never freeze the slush to the correct consistency and will overwork the compressor.
Finally, you could adjust the thickness setting (Spring against motor in most machines) to make the slush thicker, although it is unlikely that this will cause the machine to be hot.
The most likely problem is that the thickness screw tightening the spring on the motor has been turned up too much. The simple solution is to loosen off the screw. On most machines, this is achieved by turning the screw clockwise, on the Ugolini it is anticlockwise.
The Elmeco First Class uses a completely different system controlled by the Electronics Module. If the adjustment is not working then it may be a problem with the Halls Cell on the motor, or with the Electronics Module itself.
Another problem may be with the mix itself when the slush syrup has been over-diluted. This can result in pieces of ice forming which can jam in the slush mixing mechanism causing it damage or breaking a gear in the motor/gearbox.
The most common cause of this problem is a faulty solenoid coil. The solenoid coils operate valves to allow the refrigerant up to each evaporator barrel. They can overheat and ‘blow’, sometimes tripping fuses in the process. Sometimes the solenoid coil is damaged in the process and you can easily tell that it is the fault. If it looks OK then you can check the solenoid coil operation by swapping the good solenoid coil from the barrel which is freezing with the suspect one. If the problem moves then the solenoid needs to be replaced.
If the solenoid coils are operating correctly then the next most likely cause is a micro-switch which is held in place by the motor and spring adjustment mechanism. This does not apply to the Elmeco First Class where the most likely cause is the Electronics Module controlling that barrel. Check that the motor is being held correctly by the spring on the button on the micro-switch and that the switch clicks when the motor is moved to the left. It is very easy when replacing the motor in a CAB Faby machine to put the plate on the motor on the wrong side of the micro-switch. Even if the switch clicks it could still be faulty.
Finally, if both the solenoid coil and the micro-switch are operating correctly then the problem may be in the Electronics Delay fitted on some machines, particularly the Ugolini, or in the on/off switch which controls the freezing of that barrel.
The main cause of this problem is the gear motor. On the machines which use the Elco gear motor (Faby, GBG, Sencotel, Frutina, SPM) the problem is frequently a cracked or gear stripped middle gear (CABEL7). Sometimes the spiral will turn and then stop for a few moment before starting again due to this problem. At other times the spiral will turn until the mixture has turned to slush at which point it stops as the gears are worn and unable to take the load. There are other plastic gears in the gearbox which can also fail, but these are less common. The alternative gear motor manufactured by Kenta also suffers from the same problem and they have now changed the middle gear to metal leaving only the first gear as plastic.
On the Ugolini Machines which are fitted with the safety circuit (models which end in S) the problem can also be caused by a poor connection within that safety circuit. You should check that the connections between the lid and the bowl wires are clean and solid, and that the connection between the bowl wires and the flexible contacts on top of the machine are also clean and solid. Sometimes the spirals will stop turning when the lights are switched on indicating that there is a problem with the safety circuit as there is insufficient power for both the lights and the safety circuit.
Elmeco First Class machines have a split pin connecting the motor to the vertical drive shaft which can shear under load. Also, the top of the vertical auger can break meaning that the drive shaft spins inside it.
If this problem keeps on happening you need to check that the slush is being diluted correctly, not too much water. Also if the machine is being turned off at night you need to ensure that there is no ice in the machine the next day when you switch it on as this can jam the mechanism and cause damage. We recommend that the machine is never switched off when it contains slush and that when not in use you run it in chill (refrigeration) mode as this will prevent product deterioration and eliminate possible causes of damage. If the machine is not equipped with a chill mode then you can leave the machine turning but switch off the freezing, although there is a risk of product deterioration in very hot conditions, but no worse than simply turning off the machine.
Before investigating further check that the thickness setting screw has not been overtightened. You should also check that the slush mixture has been done to the correct dilution rate.
This problem is usually the result of a faulty micro-switch which is located to the right of the motor in most machines. It may simply be that the switch button is stuck in which case you can free it and lubricate with WD40. Generally, it will be faulty and need replacing. For the Elmeco First Class, the problem could either be with the halls cell on the motor or the electronics module.
The problem can also be caused by a weak/faulty gear motor which is stopping under load but then does not move against the thickness spring meaning the machine will freeze constantly.
The worst case scenario is that the valve stem operated by the solenoid coil is stuck in the open position in which case you need to replace the valve requiring a refrigeration engineer.