Thisis an old post but I wanted to ask a related question.
how is the heptane staying in my oven.
I have 3 large ovens with wet isolate on trays. when I pull vac overnight a lot of heptane is pooling in the bottom of the oven. It’s a shelf heated system. pulling with a dry scroll and a dry scroll booster.
almost every morning there’s a liter or so just pooled in the bottom of oven..
was running 30c- moved up to 35c. still trapped heptane every day. Thoughts on that?
Is the heptane cold when you open the oven? It sounds like it is just condensing at the nearest cold spot. Ideally you’d want an oven that does shelf heating and top and bottom heating to eliminate condensation inside the oven. Do you have a cold trap between the oven and pump?
You could try doing sweeps with air/inert gas to reduce it before you leave it overnight.
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Walk me through this real slow:
Closed Vac Valve
Open Vent Valve
Open door
Load trays
Close door
Close vent valve
Turn on vacuum pump (if oil sealed, allow to warm up a few minutes)
Open vent valve
Then what?
Second question: Describe your vent situation. Do you have N2 attached to your vent?
The heptane is very cold its definitely finding a cold spot. don’t usually deal with isolate. I’ll check into a heated base and shelf system.
another thing is, its usually stored open and not pre heated. I think that will help also.I’m just surprised that it could condense and then evap cool the walls and floors so fast that it runs away like that.
well close vent valve, open vac to system and start pulling. There’s no N2.
also we have 3 ovens on a manifold setup.
I did just find out the ovens are being stored with doors open. so the walls and window are cold when they start pulling vac. so im going to try to have the ovens closed and fully pre heated today. and I’ve also found heating pads to attach to the outter base to keep warm if necessary.
Then what do you do?
I send a PM out of respect. lol OMG…
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Chasing leaks, one fitting at a time. Slow down to go fast . . . . have a great day!
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Omg. Thanks for the laugh. Old post i know… that system was goofy but at least it ended up in a bucket and was reusable. Im guessing some genious removed it . Hopefully you fixed this by now . Sublimination .