Why some 2-way diverters have 2 taps, some 3?

[Possom]

Why do some 2-way diverters have two taps/dials and some three?

For example, these are 2-way diverters on the linked-to page below. Some have two taps/dials, some three.

http://canada.hudsonreed.com/bathrooms/shower-valves/2-outlet-valves.html

 

[andytw]

If it says diverter then it has 2 knobs, one for temperature and the other controls flow to one outlet OR the other.
If it has 3 knobs then one is for temperature and the other 2 control flow to both outlets at the SAME TIME.

 

[denso13]

On the three dial ones you can use the two outlets independent of each other. On the two dial one you can't - you have to choose one of the two outlets which can't be on at the same time.

 

[Possom]

So if you're using such a product between *only* an overhead shower and also a wall-mounted hand shower (nothing else), then it appears that the 2-way diverters with 2 dials will allow use of either the overhead or the wall-mounted shower at any one time. Alternatively, if I use a 2-way diverter with 3 dials, both the overhead and wall-mounted showers could be on simultaneously (though water flow would be impeded).

If using the 3-dial 2-way diverter, can the wall-mounted shower be switched off so that water is being emitted only from the overhead?

Is it especially more difficult to plumb the 2-way diverter with 3 dials?

Which option might you go for?

 

[denso13]

If using the 3-dial 2-way diverter, can the wall-mounted shower be switched off so that water is being emitted only from the overhead?

Is it especially more difficult to plumb the 2-way diverter with 3 dials?

Which option might you go for?

1. Yes
2. No
3. Go for the three dial if you want both on at the same time but you will need good water pressure/flow to feed both at the same time. Just your own preference really.

 

[Possom]

1. Yes
2. No
3. Go for the three dial if you want both on at the same time but you will need good water pressure/flow to feed both at the same time. Just your own preference really.

Thanks very much denso13, much appreciated.

Any idea what sort of bar pressure might be required to use both at same time?

My combi boiler registers 1 bar pressure on the boiler, which I believe it where it's supposed to be set at. Whereas when I test my cold water supply, I get a pressure of just over 3 bar.

I would be using an 18cm overhead shower and a 12cm hand shower.

 

[ianmcd]

the two pressures you mention are totally irrelevant, the gauge on your combi is showing the pressure of the sealed water system and nothing to do with what comes out of your taps , two different water systems