On 12 Mar 2012 17:41:34 GMT, Jim xzy wrote:

The fittings often come loose after a while when under pressure. That is
to say, the hose gets forced free of the connector. (I'm not talking
about the male and female parts of a connector coming apart.)

Can't say I've ever had that and to be honest I'm rather surprised
that they can blow apart there are the moderate water pressure you
say you have.

I wonder if it is an assembly error? The hose side of these
connectors is not "push fit". You should unscrew the collar
completely and thread it onto the hose then push the hose fully onto
the back of the connector, right over the raised lip, then slide and
screw up firmly the collar.

--
Cheers
Dave.