Split 3 way valve

[Acrisoft]

Hi

Regarding ductless mini-split systems

I have a doubt about the 3 way valve on the outdoor unit gas side

Are them all only 2 position (closed/open) with a schrader valve on the service port ?

Or are some of them 3 position, like in the compressor valves in refrigeration system ?

Moises

[Brian_UK]

They are normally only 2 position valves, some have a Schraeder, some do not.



They are not back-seating valves only open/close.

Back-seat Valve ---

[Magoo]

Are you talking about the reversing valve, if you are they are oneway or the other, no in-btween.
magoo

[Acrisoft]

Thank you Brian and Magoo

Brian answered my question

Now I know that the 3 way air conditioning valve
has only 2 positions and the 3 way refrigeration system valve has 3 positions

Most service manuals does not make it clear

This is a great forum with great techs

Moises

[Brian_UK]

Forgot to add that with the 2 position valve when you close the valve the Schraeder is open to the pipework side of the valve.

This is so that you can pressure test/evacuate etc the pipework without the condensing unit.

[Acrisoft]

Thank you Brian

But now there is a doubt left:

When I close the valve the Schraeder is open to the pipework side, as you said.

When I open the valve, does the pipework side gets closed or is the Schraeder valve that closes the pipework side by itself ?

I am asking this because you told some valves do not
have a Schraeder on them.

Moises

[Brian_UK]

No, when you open those valve all you have done is open the port between the two pipes.