Printed circuit board of water purifier

Hello vs rathore

Printed circuit boards are always vulnerable to crawling insects, including ants, beetles, spiders and cockroaches.

Insulation tape is useless, as protection of the Printed Circuit Board.

Normal practice is to spray or dip the boards after assembly with polyurethane spray, but sadly the tiny bugs have developed a liking for eating the polyurethane and all underneath it.

The only long-term solution, is to use an epoxy resin and cast the completed assembly into a block of that, with the terminal wires protruding far enough to reach the external hardware (sensor, switch, etc).

Ideally, proper efforts should be to get rid of the cockroaches entirely, remember that a dying female cockroach will eject fertilized eggs and in a day or two, you will have a new infestation.

Kind Regards....

You may try commercially available dielectric, anti tracking PCB protective coats which are meant to prevent damage against moisture, corrosion, dirt and dust, fungus and pollution. The coatings are modified acrylate and are scratch proof after drying, possibly cockroach resistant. Check for conformity to MIL I 46058C specification and if necessary for food grade qualification.

Is your PCB is protected by Soldermask or is it a bare copper board?

Anthony Gonjepa