The capacity of the fan capacitor is not enough, can two capacitors be connected in parallel?
absolutely okay! However, the withstand voltage value of the two capacitors must not be lower than the original capacitor.
Reason explanation

1. Sometimes the fan does not rotate for a long time, it is likely that the capacitor inside the fan is broken, we only need to replace the same capacitor.
For example, the original fan was a 4uF capacitor, but there are no 4uF capacitors on hand, so we can use several in parallel. The total capacity after parallel connection is equivalent to several capacitors connected in parallel,

2. The total withstand voltage after parallel connection is based on the lowest withstand voltage capacitor.
For example: 1uF and 3uF capacitors are connected in parallel, then their total capacity is 1+3=4uF. A capacitor with a withstand voltage of 300V is connected in parallel with a capacitor with a withstand voltage of 450V, and the total withstand voltage is 300V.
Most electric fans on the market have only one starting capacitor, which is connected in series with the starting winding of the motor to shift the phase. If the starting capacitor fails or its capacitance drops, it will cause the motor to fail to start. Generally, we only need to replace the same type of capacitors.

If you don't have capacitors with the same capacity on hand, you can use two capacitors in parallel, but you should pay attention to the following two points:
1. Two types of non-polar capacitors of the same type should be used for parallel capacitors. Generally, polypropylene film capacitors are used for fans.
2. The capacity values of capacitors connected in parallel are added, but the withstand voltage value depends on the minimum value, so two capacitors with the same withstand voltage value should be selected in parallel as much as possible, and the withstand voltage value should not be less than 400 volts as much as possible.