Does 3-way valve orientation make a difference?

[Spedley]

My valve is the opposite way around to most diagrams with A feeding the hot water and B feeding the central heating. The valve actuator is the right way around so I figure it makes no difference but just checking first.

 

[Steelmasons]

It will make a difference for sure..

 

[Spedley]

With power to the valve off the boiler heats hot water and with the valve manually activated it does water and central heating. The only other position is just central heating or neither and I'm sure neither would have damaged the pump by now.

 

[Steelmasons]

Really??
Who mentioned the pump (circulator)??
So why not orientate the valve???
What is the purpose of your post???

 

[ollski]

Probably put the actuator on the wrong way round to make it work in a fashion, you can do it on these valves as they operate a cam type internal which turns 360

 

[AGAS]

My valve is the opposite way around to most diagrams with A feeding the hot water and B feeding the central heating. The valve actuator is the right way around so I figure it makes no difference but just checking first.

why do you think it says B for hot water and A for heating ??????????

 

[oilhead]

I think you will find on this valve it is possible to rotate the shoe through 180o. This would make it possible to work with the head reversed. To check, remove the actuator and check the position of the stem.

 

[Spedley]

I can confirm it makes no difference. I have an old 'port' which I took apart and checked. The port is totally symmetrical except for the labels and port A is identical to port B. My actuator is pointing correctly and the key on the stem fits into the actuator (not the port) so the system works as it should.

(image TL: stem partially removed showing that the ports are closed by two sprung 'caps' - you can see rotating the shoe 180 would have no effect)
(image TR: springs removed so you can see the stem detail)
(image BL: view through stem port showing identical ports to A and B)
(image BR: image through port A showing narrowing where 'cap' closes port)