Controller of underfloor heating control valves "clogged"?

Hello everyone,

my underfloor heating has been in operation for about 6 months now, and some time ago I already noticed that the regulators of the control valves are extremely dirty. It looks as if it were algae or something.

I don't think this is normal. But is it common? Could something have gone wrong here?

Regards

This is called biofouling and occurs, when it appears so quickly after startup, due to incorrectly filled systems, leaky systems (oxygen ingress), or also non-noble components in the system.

Thank you for the answer. That doesn't sound good! What can be filled in incorrectly there?

Contaminated water, air bubbles, ... You can get a lot wrong there.

What can be filled in wrong there?

Simply everything. Anyone who didn't pay attention in chemistry and then became a plumber/heating technician... ends up producing something like this.

Complain? You probably have little chance there as well, right?