Reversing valve replacement?

[Drew]

Hi,

just wondering if anyone has a good technique to replace a reversing valve.
they are sometimes impossible to get to and then there is no room to unsweat the pipes. This is generally on bigger split units. I'm having to remove compressors to try and make it easier.
anyone got an easy way?

thanks

[The Viking]

Cut the pipes where they are easier to get at then move the "stumps" over to your new valve (remembering to wet rag it and flush with OFN as you are brazing) then just use straight socket joints as you brace it back in to the system.

:cool:

[Drew]

So much brazing ....... What else can you do though?
Thanks.

[Drew]

Low heat not to heat the valve too much or high heat to do the job quickly?
Wet rags cut in strips to wrap around pipes.

[CraigF]

As said before, Cut the badboy out and sweat off the remaining parts, then wet rags, wet rags, and more wet rags as you braze in the new one (plus OFN of course!!). One of them foil backed flameproof sheets is also good as you can mould them to suit the application and protect any sensitive bits. remove any probes etc. and cabling to leave as much room as possible. Personally, I hate doing them!!

[The Viking]

Always braze with the correct heat for the job, start with getting the pipe nice and (dark)red then move the red band on to the joint.
Trying to use a lower flame to protect the equipment results in the brazing taking longer, allowing for more heat to be transferred and the bits you are protecting therefore getting warmer.

Another hot tip (pun intended), as you are doing the joints closest to the valve outside the unit you can even submerge the valve upside down with the joints sticking up in a tray of water to protect it. (As long as you don't get any water in to the joints or the valve...) When you get to brazing the whole assembly in to the unit you have nice long stubs to wrap up with wet cloths to ensure the valve stays cool.

:cool:

[HVACRsaurus]

Braze up the bottom one first, then rig up a garden hose (cable tied in place) trickling water over the valve - then take as long as you like..