nitrogen purging

[gleeary]

hi
can any guide me
i am starting vrf shortly what is the proceedure for nitrogen purging

[Kev M]

You shall have to blow a small amount of OFN through the pipe work when you are brazing roughly 5 psi. Connect a hose to your regulator and put it into the end of the pipe you are brazing.

[taz24]

hi
can any guide me
i am starting vrf shortly what is the proceedure for nitrogen purging

Hi mate.

Its not specific to VRF / VRV. You should purge oxigen free nitrogen (OFN) through all fridge pipework that is being brazed. It is good practice and stops the build up of oxides (carbon, sooty deposits) forming on the inside of the pipe.

taz.

[boy]

gleary,

standard practice on copper pipe brazing is to have a flow of 10 psi dry nitrogen on the pipe so not to oxidize it.

regards,

[monkey spanners]

I've got a flow meter for about fifteen notes from a welding supplies shop/Boc agent which is intended for co2 when mig welding, works a treat with ofn, also got a cheap low pressure regulator to go with it, just set the flow at X litres a minute to suit the size of pipe, bigger pipe-more flow. Saves ofn and you actually know its flowing rather than just pressurising the pipe as the little bead rises in the tube with the flow. Will try and post some pictures tomorrow. Looks professional too imo.

Jon

[Brian_UK]

Strange that when people start installing VRV/VRF they feel that they should start using OFN.

Is it them big scary pipes