Hi,
I bought a second hand memmert vacuum oven yesterday. It’s far better than my cheap oven, came with a vacuum pump and was a steal (300€ for both).
Pump looks a bit old and does not have any brand label anymore. I was surprised because it looks oiless and I never had this kind of pump. I finally identified it as this make: 
So it’s a membrane pump, without butane compatible membrane.
I guess I can’t use it to purge bho. Is there any use in our field?
Thanks
What makes you think it s not compatible membranes ?
There’s a machine plate on top side of the switch should have all the info you need
Would not be suprised if it s a knf brand
If so your lucky
Like I said proper brand label is missing and that’s the first time I see this kind of pump. I’m only used to rotary vane pump. I assume the worst as there’s no point in destroying a perfectly working pump and couldn’t imagine I’d be that lucky. Better safe than sorry. Mine is older than this one and the technical label is almost faded. I googled oiless vac pump, and tryed to find closest looking one. Mine is older tho. While looking I’ve read that membrane pumps were sensitive to many solvent. Hence the assumptions.
Like I said a lot of adoption as it’s the first time I’ve got that kind of pump.
However, assuming it’s a knf pump helped a lot to decrypt the almost faded technical label and identifying the pump.
It’s a N.035.AV.18 from knf. I can tell it’s old but have been serviced by a legit lab supplyer. It’s aIuminium head, fpm membrane and SS vane.
Fpm is viton, right? So I guess I can use it with the memmert VO in order to purge.
By the way while reading specs sheets, it looks using it on already vaacumed space is a big no-no. Is that true?
What kind of servicing should I expect to deal with?
@Roguelab Thank you for your help. Also I’ve got it because of you as I’ve read one of your post one time where you linked to machine-seeker. It made me realise I could find some real nice stuff 2nd hands in my area. Next purchase an ULT freezer. So big thanks for all your helpful posts!!!
Edited trying to make myself clearer as my English isn’t really good. Added a pic as well.
Try using the keyword “diaphragm” instead of membrane. Open it up and inspect the diaphragm for any markings. It may also give you an idea how easy they are to service if you find replacement diaphragms. If you get replacements, go for buna or viton. PTFE doesn’t pull as deep of a vac.
Tanks a lot. Using membrane did point me to N2 membranes or filtration related threads indeed.