vacuum level does not effect decarb. you are NOT converting THCA to THC because you are sucking too hard. it’s about activation energy to break a bond. which does not change like boiling point does under vac.
you might be boiling some of it off, but not a whole lot (based on temps and vac levels used for short path, not personal experimental data).
sucking too hard will absolutely lose more terpenes. your logic is sound on purge speed as well.
Thanks @cyclopath the part about thca converting i hadn’t put together, makes complete sense though!
I like where you are going with the more gentle vacuum. Do you have a newer oven with the dial gauge or digital? You are probably seeing more vacuum than that. The gauge is confused by the elevation, not the pump.
Another thing you could do is backfill with Nitrogen instead of closing the vac valve. This way, you are still removing the gas from the system but not at such a low vac level. Just put a regulator on an N2 tank and use .25" tubing to attach to the back of your oven on the vent port. Easy Peasy.
NITROGEN IS AN OXYGEN DISPLACER. YOU CAN DIE IN A ROOM FULL OF N2. DON’T DO THAT. ONLY USE N2 IN A WELL-VENTILATED ROOM.
What psi do you recommend for the backfill? Thanks
Thanks so much for the reply, they are all the digital touch screen, I add about 5 inches of mercury to whatever the gauge is at due to elevation. We have pitched it to the bosses so heres for hoping they think its a good idea too! It seems so much cleaner to me to use the n2 backfill as well,
At the very least, get .25" tubing and run a length from the vent port on the back around to the side of the oven. Tape it there. The likeliest place for dust, pollen, particulates is behind the oven. Every time you vent, all of that dust is sucked in with great velocity to rest on your beautifully-purged slab. just by bringing the tubing around to the front, you are more aware of the possibility for contamination. If you are feeling fancy, pick up one of these for the end:
Happy Purging!
Catherine
Set to 1-5 psi. The regulator will provide that psi up to its max cfm. Go slow on the oven vent valve, otherwise you can blow around your product. Dont get distracted when doing this, If you forget about it you will be rewarded with a dull pop as the door gasket hops off from its gland.
Thanks @Soxhlet I will give her a go.
when i got my AI oven we had to calibrate it a few times and the temperature was all over the place. Turned out it had a faulty temperature controller so they sent me a new one. One thing they recommended is getting a cheap oven thermometer and putting it on a rack that way you can see the temperature (roughly) without opening the door. I keep mine in there on a spare rack just to make sure im in the right ballpark.
Thanks again everyone for the posts, @Sidco_Cat that is a WONDERFUL idea, I will be implementing that this week.
Hey I’ve discovered my AI ovens are off about 6-7 degrees F. Just wondering what the lowest temp I should be worried about decabing starting to happen?
You can look in your manual or online, you can re calibrate your oven to get the temps right. The higher the temp the faster the decarb. That being said, I purge our ethanol shatter at around 120 F and only see about 5% decarb over 2 days.
I have a semi-relevant question.
Seems everyone is using dry-scroll pumps, but these aren’t rated for use with pyrophoric gases (hydrocarbons, etOH)
How do you ensure safety when using a vac oven/pump to purge butane from extracts?
Do vac ovens need to be in c1d1 rooms or can they operate in normal lab space?
Thanks,
Phil
do you ever make ETOH crumble or sauce?