Fernco couplings on pressure pipe

I had to have a washing machine water supply box replaced and the plumber used Fernco couplers to connect supply stubs from the box to the hot and cold water copper supply pipes. Is this acceptable? He said it would be better than a traditional coupling. Is it ok to use Fernco couplings on pressure pipe applications like this? Should he have soldered the connections or used compression couplings?

Call his boss and tell him what was done!!!!!!!!!

Fernco's come that small¿ There are some water systems that use "hose clamps" but by all means this job should've either been sweated or PEXed with approved connections. Post us a pic so we can have something to add to the Pig Slop thread!

Fernco

It depends on what you mean by "Fernco couplings". The traditional Fernco, which is what most people mean when they use the term, is a drain connection which would be totally inappropriate for a water line, assuming you could even find one that size. There are other connections for copper tubing and their desirability varies according to which and where they are used. A picture would help in the diagnosis.

I was way off. I opened the wall back up and found he used a Fernco on the drain and PEX on the supply lines. I thought I remember him saying it was all Fernco. Sorry for wasting you guys' time. Thanks for the advice though.