Cleaning coils: counterflow chiller & HERMS

[sibelman]

We can't see or reach inside coiled tubing, so we circulate hot PBW or Oxiclean solution to rinse/scrub these coils. Then rinse until the rinse water runs clear. But does it?

I find it hard to convince myself I've thoroughly cleaned these widgets. Hot rinse water still shows some bubbling exiting the coil and splashing into a tub, even after several gallons of rinsing. Cold water: not so much. Especially evident with the copper counterflow chiller.

Thoughts, anyone?

 

[Jag75]

I think what your seeing is o2 bubbles forming in the water. Same as pouring water into a cup . I'm just taking a stab at it . You know if the pbw is fully rinsed by feel. Pbw water is slick .