Non-invasive current sensor noise problem
OK so you've got this pump that presumably has got hundreds of turns to create enough magnetism to rotate the armature. The pump takes 250mA and the magneto motive force (MMF) is amps multiplied by turns. The magnetic field emanating from this pump has a driving force of 25 ampere turns (that's 0.25 amps x 100 turns) and maybe there are more like a thousand turns. It could be as high as 250 ampere turns.

On the other hand, when you feed a single wire (that's one turn) through the CT to measure maybe 40 amps peak\$^1\$ of household consumption, the MMF is 40.

You hold the CT close to the pump and you get a reading - are you still surprised? It's called leakage flux and the CT's core is not a perfect rejector of leakage flux that hits it.



\$^1\$ this will be different depending what your AC voltage is.