Thermostatic mixer/diverter/flow valve.

[piperca]

I am installing a fixed shower head and a hand shower unit in my new shower. I know I will need a 3 port diverter to switch between the two. If I use a thermostatic or pressure balance mixer, like the Hansgrohe Axor Carlton, do I need a flow valve, also? I really like the look of these single-handled units!

Mixer:

Diverter:

Flow:

[jadnashua]

Some separate the temperature control from volume control. Assuming this does, then yes, you need a volume control to shut water off.

[EuroPlumber]

Hansgrohe offers several solutions to your question.

The thermostatic valve you want to use mixes the water only, so you need flow control also. For a showerhead and handshower setup you can use the Thermo valve with their Triostop diverter which allows you to control flow, divert to either, or share both on at the same time. Then you only have two handles to deal with.

The second solution is to use a volume control valve for the shower head, and a Fix Fit wall outlet for the handshower. The Fix Fit outlet controls flow for the hand shower. The nice thing is that if you are putting the handshower near a bench (the ladies like this for shaving) you will have the flow control at the hand shower in easy reach of the seated bather.

[JohnIrish]

I have been researching the same question and I can tell you what I learned so far. I am not a plumber so verify what I think... EuroPlumber gives some great information.

Hansgrohe also does make the Thermobalance III valve. This is a temperature valve and a diverter in one. This will let you switch between the shower and handshower or use both together.

I do not understand how much volume control is available on the Hansgrohe Thermobalance III valve. I called the Hansgrohe technical support line and they told me it would also control volume. Call me a skeptic but I am not sure if I believe them. That is not what I have been reading in some other forums from actual users. I am still looking into that.

Delta makes a 17T series valve that will control volume and temperature. They also make a 3 way 6 position diverter you can use for multiple devices. Volume would be controlled off the main control but then it would affect every shower head equally.

The simplest solution seems to be a Thermostatic valve with individual volume controls. However, a stand alone Thermostatic valve seems to be about twice the cost of one of the combination valves (like the Thermobalance III).

[EuroPlumber]

Carlton is in the AXOR range of products. This is Hansgrohe's Lexus brand. The ThermoBalance line of valves is the Toyota version Hansgrohe line. Both are dependable, but AXOR has more performance and style.

ThermoBalance III is capable of running 3 items, controlling flow on port 1&2, but not on port 3. Piperca said he only wanted to run 2 items in his shower so I will explain how he can do it with ThermoBalance.

ThermoBalance II can run two items, but you cannot run them both at the same time. The valve lets you set the desired temperature and control volume to each outlet by turning the handle either clockwise or counter clockwise from the off position. All of this is controlled on one knob and lever combo handle. Basically two handles on one valve stem. Sounds impossible, but it works great.

Thermobalance III can be used for two features but you have an extra outlet. The unused outlet should not be capped or plugged or it can damage the ceramic valving. So the way to pipe it is to run the bottom outlet 1 up and tee into outlet 2 riser that feeds the shower head. Outlet 3 pipes to the hand shower. This setup allows the shower head or the handshower run together or seperate. There will be an ability to control volume to the shower head and to bias the handle in the shared position giving either the hand shower or the shower head more pressure and the other less pressure. But the handshower must be full on when it is running solo.

You could share both and get volume control on either if you piped outlet 1 and tee into outlet 3 riser, but you will get cross flow through the valve until it is trimmed out. This is okay for new construction, but crossflow on a remodel can be a hazard.

[piperca]

Thanks for the responses.

For simplicity we decided to go with the Thermobalance II. We haven't used it yet, since I am still working on the tile, but hope that it suits our needs. The wife likes the handshower and I'm not fussy. I liked the look of the Axor stuff, but, in the end, I couldn't justify the price.

[miramax]

You could share both and get volume control on either if you piped outlet 1 and tee into outlet 3 riser, but you will get cross flow through the valve until it is trimmed out. This is okay for new construction, but crossflow on a remodel can be a hazard.

To EuroPlumber or anyone who knows the answer -
We would be using Thermobalance III to run two items (overhead and handheld showers) and would like to have the capability of volume control for both by piping the valve as you have mentioned. Can you explain why cross flow on new construction is okay but might not be on a remodel? We will be doing new construction, btw.

Oh and just to be clear about this, outlet 1 should be teed into outlet 3 (instead of outlet 2), right?

Thanks in advance.