Hi, I've just installed a Triton Cara shower; I went through the commissioning process, turned on the water and mains supply, but no water is flowing through the unit? I know the water has reached

If the mains water pressure is good supplying the shower unit the restriction must be within the unit or the hose and shower head. Try removing the shower head and if no better the unit should be investigated.

Instantaneous shower units are designed for connection to the mains water supply. They can be connected to a header tank supply but a booster pump will probably be needed unless the header tank is at the top of a very tall house.

Could be a pump jam, do you have hard water ? Could be scale build up.
Is the shower head blocked ? Unscrew just the head (leaving the hose line attached to shower) and try again. If that is the blockage, then clean it with descaler.
Also check you have a good pressure on your water supply going in the Triton. Low pressure can set off safety switches. Again, check for blockages.
Check also for breaks in wiring and check there is no water ingress at any and all connections.
Is it an old unit ? Is it serviced regularly ? .......finally....
are all the settings set to MAX ? if so then use lowest setting first.
If it works then move settings up gradually until it trips.
Any filters need to be checked if possible.
Good luck Red.

The installation must be in accordance with
Water Regulations/Bylaws.
To ensure activation of the heating elements, the
shower must be connected to a mains water
supply with a minimum running pressure of
100kPa (1.0 bar) at a minimum flow rate of eight
litres per minute (nine litres per minute for the
9.5kW rated model).
For all units the maximum static pressure must
be no greater than 1000kPa (10 bar)
.
If in any doubt, the pressure should be checked.

CHECK YOUR POWER SUPPLY BOX MAKE CERTAIN THAT IT IS INDEED ON IF SO IT MAY BE A BAD CIRCUIT BRAKER MAY NEED TO REPLACE IT.

contact the guy that put it in.

Your supply pressure is too high for the unit, it is too much for the solenoid to shut off, you need to put a pressure limiting valve inline.

there is a cut out unit on top of the element *** unit which is to prevent damage to elements if the water supply fails but i have 3 of these fail down to use have checked the triton spares and the only show it with the element unit cost over £100 you can bi pass it with out any problems just make sure always turned off at pull cord when not in use or phone to see if you can just buy the cut out if you cant its shame on them good luck spares number 08449800745

It is probably the water solenoid valve wich is stuck or bunt out.
If it is brand new, maybe you have warranty.

the shower head is clogged,..easy to clean. just take the head off, and clean screen

sounds like the pump is broke. better off just replacing whole unit unless you order new pump from triton.