3 port valve - which way is flow?

[koiman]

Is there any standard convention for which ports of a valve are open in relation to the flat on the valve spindle?
I have a 3 port zone valve (unknown make/model), controlled by an actuator. The actuator linkage broke and, now that I am replacing it, I can't fathom out which position it should be in? When the flat on the spindle points to a port, is that port open or closed?
Thanks.

 

[townfanjon]

They usually have an A for heating and B for hot water

 

[townfanjon]

Sorry the bottom of the Tee is the flow in to the valve

 

[koiman]

OK I think I've worked it out by trial and error. For this valve anyway the flat on the spindle points to the port that is closed.

 

[buckley plumb]

b for bath water always taught at college

 

[koiman]

OK I think I've worked it out by trial and error. For this valve anyway the flat on the spindle pints to the port that is closed.

 

[kay-jay]

ab is flow
a is heating
b is ho****er
default setting is open to hw

 

[oz-plumber]

Is 'ho****er' a banned word

 

[oz-plumber]

Is 'ho****er' a banned word

Hot-water is a banned word

 

[PlumbBobBob]

no the word in the middle is the banned word lol

 

[Masood]

Is S****horpe also banned?

 

[PlumbBobBob]

Is S****horpe also banned?

you can use it just it will look carp

 

[SJB]

Doing my apprenticeship in the Black Country was taught "A fer yer 'aytin B fer boffrooms"