Chris J Dixon wrote:
A word for the unwary, unless it is just me

[snip]

3-way - no technical notes. I now know that this has four ports,
two of them inputs, one to be blanked, and two outputs.

5-way - no technical notes. I now know that this has five ports,
two of them inputs, one to be blanked, and three outputs.

Can anybody see the logic here?

Chris

Not really. If the valves are taking the already-mixed water from the
thermostat, why do they need more than one input?

Neil