This is for an arduino based "smart dehydrator" . Noise is from a fan motor inside a dehydrator. This 5v bus will power a Dallas temp sensor and Dht22 humidity sensor and 3 buttons for a menu on i2c LCD. There are phantom button presses. The project creator used a snubber but also recommended these caps to be used in the 5v bus.Yes, but note the proper polarity of the large electrolytic capacitor.
What kind of noise?