Purging an R290 system before brazing

This is the steps i take to ensure there is no r290 in a system before I light a torch. Yes that stub with an access port is from the manufacturer. Contrary to popular belief, it is not ILLEGAL to leave access fittings on r290 or R600. I demonstrate cutting the high side process tube and venting the R390. I then purge with 50psi of nitrogen to clear the remaining R290 out of the system. This time it took a few tries but eventually I cleared the system of any remaining refrigerant. I used my Inficon gas mate to ensure i was clear and ready to braze. Remember to do this in a well ventilated area, such as outside or under a hood. If that can not be accommodated, I use a temporary tap and a 50ft house to get the R290 away from my work space. I have also took a recovery cylinder and pulled it into a deep vacuum, and used it to pull r290 out and push it into the cylinder with nitrogen. You will not get it completely clear with this method but it will get the bulk of it out.

[@filter4now]

Can you smell R290? Once i got some dust off (which is 152a or 134a usually) but this brand wasnt - it stunk. Dusted my whole computer then lit a candle - WT...F? It was "butane, isobutane" mix (

[@letmevibe8318]

Are the lines aluminum?

[@CommercialKitchenChronicles]

Nope

[@shawns6135]

390?

[@CommercialKitchenChronicles]

Fat fingers, it is fixed lol

[@SULK81]

Factory access port on a R290😂

[@CommercialKitchenChronicles]

Yep multiple manufacturers do it