We are the UK's largest official stockists of Trevi shower spares, with most Trevi spare parts ready for same day despatch. We stock shower spares for Trevi mixer showers and Trevi bar mixer showers, including Trevi shower headsTrevi shower head holdersTrevi shower hoses, and internal spare parts. There are many Trevi shower valves in our spares library. 

Perhaps you have identified yours as either a Trevi Boost or Trevi Therm, but you're not sure which one it is?

These were very popular showers and operate using a unique gear/cog assembly on the flow control side. 

Trevi Gear box assembly for the Trevi Therm Mk2

This gearing turns the identical anti-clockwise close cartridges in the same direction using a spindle and gear cog system, allowing a balanced flow of water into the shower mixer valve.

If you are experiencing problems with the showers flow or temperature regulation, the gearing may have become jammed or damaged.

This would stop the cartridges from opening or closing fully when the flow handle is rotated. As with any flow cartridge, the cartridges can also become seized or worn over time.

It's worth checking these cartridges and gearbox for the above issues first when troubleshooting.

You can find the flow cartridge for these showers here

These are sold as single cartridges, although it is recommended to replace both flow cartridges at the same time when servicing the valve.

For more help diagnosing more general faults with showers, see our Fault Finder

Which Trevi Therm or Boost do you have?

We are frequently asked how to identify these showers. There are a few versions and they do look very similar! Read on below for some tips:

Step One: Find the colour of temperature override button on the temperature control knob

Chrome, silver or red? - You have a Trevi Therm 

Confirmed Trevi Therm? 

Step Two: Ascertain which version you have (Mk)

Does your temperature control knob have 2 or 4  flat edges on the handle? (Ignore the flow control handle for this)

4 flats on the handle - Mk1 

2 flats on the handle - Mk2

Therm Mk1 models here: 

Therm Mk2 models here: 

Black or grey temperature override button, like the below? You have a Trevi Boost Mk1.


The later Trevi Boost Mk2 has a different handle design here.

Points to consider:

  • If the handles have been changed at some point before, it's not unusual for the two handles on your shower to have been mixed up with another version.

To identify your model, just pay attention to the temperature side. Although to maintain a consistent design, you may want to also change the flow control knob to match the number of flats of the temperature handle.

There is also a very similar Trevi shower with traditional style handles, see:

Trevi Traditional Mk1

Can be distinguished by the below cover plate, the screws are visible.

Trev Therm Traditional E3115AA (Later model)

Can also be identified by looking at the cover plate, the screws are covered by a trim plate on this mod.

Need some more help Identifying a shower? 

See our article: Need help identifying your Shower or Part?