Tandem 2 port valves?

[Bunker]

Hi chaps. Any idea why the installer would do this? Both NC.
Cheers

 

[SimonG]

Unvented cylinder, he already bought 2 for his S plan and the cylinder came with one so fitted it as it was there?

 

[Killy Bing]

some sort of extreme safety interlock ?
are both connected ?

 

[tamz]

Because he is a halfwit.

 

[bigman]

Because they had dhw written on both of them

 

[Chalked]

To be sure to be sure........

 

[Bunker]

Perhaps one opens the other one... 🙂

 

[Meady]

He probably thought incase one fails there is still the other one there as a back up 🙂

 

[Reg Man]

One valve for the UVHW overheat thermostat? the other for the UVHW operational thermostat?

 

[solutions]

How its wired will tell you its function if it has a deliberate one.

 

[PlumberDom]

How else are you supposed to balance the flow from the DHW and the HTG? I often find myself putting 5 or 6 in.
;-)