If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.
Special Thanks To:
Aaron Holmes
Aaron Wheeler
Adam Horden
Alan Scrimgeour
Andre
Andrew Haynes
Anonymous000
asabase
Austin Weil
barney
Barry
Bert Hickman
Bill Kukowski
Blitzorn
Brandon Paradelas
Bruce Bowling
BubeeMike
Byong Park
Cesiumsponge
Chris F.
Chris Hooper
Corey Worthington
Derek Woodroffe
Dalus
Dan Strother
Daniel Davis
Daniel Uhrenholt
datasheetarchive
Dave Billington
Dave Marshall
David F.
Dennis Rogers
drelectrix
Dr. John Gudenas
Dr. Spark
E.TexasTesla
eastvoltresearch
Eirik Taylor
Erik Dyakov
Erlend^SE
Finn Hammer
Firebug24k
GalliumMan
Gary Peterson
George Slade
GhostNull
Gordon Mcknight
Graham Armitage
Grant
GreySoul
Henry H
IamSmooth
In memory of Leo Powning
Jacob Cash
James Howells
James Pawson
Jeff Greenfield
Jeff Thomas
Jesse Frost
Jim Mitchell
jlr134
Joe Mastroianni
John Forcina
John Oberg
John Willcutt
Jon Newcomb
klugesmith
Leslie Wright
Lutz Hoffman
Mads Barnkob
Martin King
Mats Karlsson
Matt Gibson
Matthew Guidry
mbd
Michael D'Angelo
Mikkel
mileswaldron
mister_rf
Neil Foster
Nick de Smith
Nick Soroka
nicklenorp
Nik
Norman Stanley
Patrick Coleman
Paul Brodie
Paul Jordan
Paul Montgomery
Ped
Peter Krogen
Peter Terren
PhilGood
Richard Feldman
Robert Bush
Royce Bailey
Scott Fusare
Scott Newman
smiffy
Stella
Steven Busic
Steve Conner
Steve Jones
Steve Ward
Sulaiman
Thomas Coyle
Thomas A. Wallace
Thomas W
Timo
Torch
Ulf Jonsson
vasil
Vaxian
vladi mazzilli
wastehl
Weston
William Kim
William N.
William Stehl
Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Registered Member #514
Joined: Sun Feb 11 2007, 12:27AM
Location: Somewhere in Pirkanmaa, Finland
Posts: 295
Nik wrote ...
Crimp the lines shut so you don't dump all of the freon out. Just get some heavy pliers and crush/fold the pipe before you cut it (on both sides).
That won't do any good, I'm afraid. It might save you from getting sprayed with boiling refrigerant and oil vapor, but it won't stop the good old CFC's from leaking into the atmosphere. Any crimping made on copper will be insufficient to contain the refrigerant for any considerable amount of time.
Now, should one care about leaking refrigerant gases into the atmosphere is another matter...
Registered Member #1321
Joined: Sat Feb 16 2008, 03:22AM
Location:
Posts: 843
What about using a water aspirator pump? It would be cheap, it would pull down to the range of 10 to 20 torr or so (I think), it could pump water vapor, and it uses no oil or other potentially contaminating substance. You could hook it up to a pump and a tank and make it recirculating, thus avoiding having to use a lot of water.
Registered Member #2099
Joined: Wed Apr 29 2009, 12:22AM
Location: Los Altos, California
Posts: 1716
... I will just wait for someone to throw out a fridge and take the pump then. Hypotheticly if someone were to have utter disregard for the laws the EPA has set in place and cut the freon line to discharge it ...?
That would be like peeing in the swimming pool, to save yourself some time and trouble.
We know there are people who do it, and are glad that most people don't.
Registered Member #1721
Joined: Sat Sept 27 2008, 08:44PM
Location:
Posts: 136
Hello:
Moisture is the enemy of vacuum pumps, this said however there are numerous ways of dealing with reasonable amounts of moisture in a vacuum system.
Most rotary vacuum pumps have a gas ballast which mixes in a little air durring the compression phase of the pumping cycle, thus preventing the condensation of any moderate amounts of water vapor. So with the ballast on, you are fine with some water vapor. Changing the oil often is also recomended.
If there is a lot of water vapor like in vacuum drying, then a trap of some kind is the only way to go. Stainless steel pumps were tried, but most makers gave up on SS due to the SS galling problem, this is the same reason military machine guns are not made from SS. For vacuum pumps instead they use graphite or ceramic vanes, or Teflon coatings ect. I know that HyVac / Cenco tried for years to make a SS pump, and all of their attempts failed.
For the vacuum level you are talking about I would use an aspirator / water ejection pump, it will get you to 26" vacuum with no water issues, and no moving parts. Also keep in mind cooking is related to temperature, and NOT to the boiling process. So under vacuum water may boil at room temp, but it will never cook the food.
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.
Vacuum Pump
