The 6 Best Vacuum Ovens
This wiki has been updated 3 times since it was first published in July of 2019. Vacuum ovens are suitable for diverse applications, from the medical and aerospace to the cannabis and electronics industries. They are designed to extract liquids and gases from a range of materials and can be massive in some uses, though our rankings are focused on smaller options of two cubic feet or less. When users buy our independently chosen editorial recommendations, we may earn commissions to help fund the Wiki. Skip to the best vacuum oven on Amazon.
July 16, 2019:
Vacuum ovens use pressurized environments and controlled temperatures to remove gases and liquids from a variety of materials. These devices have been around for years, and have wide-ranging applications. In the electronics industry, they’re used frequently during the manufacturing process for semiconductors and circuit boards. Modern medical technology relies on them to cure prosthetic joints, catheters and synthetic heart valves – that otherwise will bleed harmful chemicals into their recipient over time.
Professionals in aerospace technologies depend on vacuum ovens to simulate space-like conditions. Prior to deployment, any item that’s going to be sent into space needs to be subjected to vacuum conditions to accelerate its natural off-gassing process. Without taking this precaution, after take-off, every item on the spacecraft would start off-gassing simultaneously under increased pressure. Chemical reactions resultant from the amalgamation of these gases could result in condensation, corrosion or even fire aboard the spacecraft in question.
More recently, with the legalization of marijuana in Canada and several of the United States, vacuum ovens have become staples in the cannabis industry, where licensed producers – who typically produce crops under indoor grow lights – use them to purge harmful solvents from butane hash oil (BHO) and other pot extracts.
As the name suggests, vacuum ovens are essentially vacuum chambers – only with a temperature control feature. Although many of the vacuum ovens utilized in industrial applications might be massive by comparison, most the models made easily-available (or at least reasonably affordable) to the average consumer aren’t much bigger than a microwave.
A few things to keep top of mind while you’re shopping:
What sort of heating system does it have? In many circumstances, vacuum extraction can be a fickle process, demanding precise control. A major differentiator between products in this category is how even the temperature uniformity is within the oven chamber. It seems like the options that boast the best temperature uniformity are the offerings that combine five-sided heating (radiant heat emitted from the top, bottom, left, right and back wall of the chamber) and thermo-conductive shelves – which seem to be typically made of aluminum.
An alternative system that’s known to be inferior to five-sided (or even four-sided – no back wall) heating is direct heating through the oven’s shelves, which essentially act as elements in this case. Some offerings – including the inexpensive Geindus Drying Chamber – actually incorporate a traditional element (similar to a common electric stove) into its chamber. Although the company boasts how this configuration improves the unit’s heating time, it should be noted that this method is likely to produce poor temperature uniformity, and should be avoided if your budget permits it.
What sort of capacity do you need? Although most the smaller-style units out there (like the ones ranked on this page) seem to fall into the common .9-cubic-foot and 1.9-cubic-foot categories, there does seem to be some level variance in how many shelves these units are designed to accommodate. If the samples you’re putting under vacuum are all relatively flat, an oven with 12 shelves will hold 50% more than an oven with eight shelves – even if both ovens are 1.9-cubic-feet.
How much control do you need? It’s simple enough to set the temperature on these machines, but sometimes these extraction processes can take days, and require intermittent fluctuations in temperature. If taking care of that whole process, the whole way through, manually, stopwatch in hand doesn’t sound like your cup of tea, you might want to consider an option like the Thermo Scientific ELED 3625A – that incorporates a seven-day timer with a maximum of eight daily events into its design.
Regardless of what kind of lab work you’re involved in, there’s always a risk involved when you’re working with high-vacuum conditions. Be sure to familiarize yourself with your oven’s user manual and observe all recommended safety protocols.