Low water pressure on brand new Mira shower

Hello

We've just replaced an old Redring California which was losing pressure and heat. We now have a Mira Sport 7.5 Kw (cold water feed).

The very first shower I took with the Mira was great, with plenty of heat and much more pressure than the Redring. However since then the pressure has dropped significantly.

We have a combi boiler, but the shower is cold water fed so I'm assuming that has no bearing. I know that the shower isn't the most powerful at 7.5 kw but at it's best our old shower had better pressure, as did the Mira on the first use.

Any ideas as to why this is happening would be much appreciated.

Thanks

 

Just a quick follow up on this in case anyone else has a similar issue:

The plumber came back and did a very thorough check of all the things mentioned above plus more and found nothing wrong, so I booked a Mira engineer (got an appointment for about 5 days later) and it turned out to be a fault with the solenoid, and the device that regulates the heat was mechanically not flipping as it should, which explains why the first shower was great then the issues arose. The Mira guy fixed it (free, under warranty) and all is now well.

Thanks again for the help.