All you wanted to know about a chamber vacuum sealer, but were afraid to ask
I've been wanting a chamber vacuum sealer for a very long time, actually somewhere in the order of the last 35 years or so when I saw someone who had a much more primitive chamber vacuum machine. For most of that time I've had a couple of different Foodsaver type machines, one of which I just wore out. By Foodsaver type I mean the type of machine that draws a vacuum from the bag and then seals it all externally. Foodsaver is far from the only provider of these types of machines, but did make them popular.
So why get one of these? Well first off I'll say there's just a few pros and a lot of cons to getting one of these machines, so most people are going to want the foodsaver type. The chamber type is much bigger, heavier, and more expensive. The advantage is the ability to vacuum seal things with liquids without any work arounds and it draws a stronger vacuum. Both of these things are helpful if you do a lot of sous vide, and I do.
I'm not going to post a link to the one I got because evidently some people don't like that. It's easy enough to find if you do a search on the brand from the pic. The model number is DZ-260C, but that is mostly meaningless because for whatever reason lots of exporters use the same model number for different products. There are a few youtube reviews of the one I have, and all I've seen are positive. My impressions of this one are very initial. I've only had it up and running for a few days. There's several of these on the market from many different sources. From what I can tell all are made in China and there doesn't seem to be much in the way of quality control between any of them. If you do get one, my advice is to go by price and what fits your needs and space. The one I got was about half the price or less compared to some of the more promoted brands, so that was my primary consideration. Other considerations was the size needed to do larger bags and the customization of the vacuum and seal profiles.
One of the things I just could not find out about this one before I bought it was how it was going to fit in my space. I really needed it to fit under my cabinets and there were no dimensions I could find that were of much help. For reference my countertops extend 25" and there's 17.5" from the countertop to the bottom of the cabinet. The cabinet itself extends out to 11.75". With the top open the lid does impact the cabinets, but just barely and it doesn't affect the operation at all. However, if your countertops do not extend as far or your cabinets are lower, you probably wouldn't want this one.
Chamber vacuum sealers fall into two different types depending on whether they have an oil filled or oil free pump. I would have preferred an oil free pump because I'm not using this thing all day long and either way I can expect many years out of a pump. An oil free pump wasn't an option with this manufacturer, so I got what I got. The down side is you have to fill it before use and should change the oil about every 250 operations which for me will work out to about 6 months or so. It's not hard to do and I would guess will take about 15 mins or so. The other down side is you get a little bit of odor from the oil when using it. I wouldn't call it unpleasant, but it is noticeable. Supposedly oil filled pumps are quieter. It does make less noise than my foodsaver type, but not much.
Right away I noticed a QC issue with mine. You have to take off the back cover to fill the pump with oil. The screws holding the cover on were machine screws and they should have been sheet metal screws. It wasn't a big problem as I had some sheet metal screws of the right size, but getting the other ones off took a bit more time. Otherwise the machine seems well designed and implemented.
Some of these machines have an accessory port in which you can attach a hose to a mason jar type device that can seal jars. This machine doesn't have one. You can put jars inside the chamber, but with this one you are limited to 4" of height. You can lay them down, but that presents other problems. So the max size jar you can stand up is 8oz, provided it is less than 4". Not a big deal for me, but might be for those who want to do a lot of jars.
Some other things this machine has which I like is you can very easily set vacuum time (roughly corresponds to the amount of vacuum as indicated on the gauge), length of seal and rest times. There's also an option to single or double seal the bags. I haven't even tried the double as the single seal works better than the foodsaver types I've used. There's also an emergency stop button which I consider a necessary feature which some machines lack. The seal bar in this machine is in the back. Most have them in the front. With a taller machine as this one is, I think it works better in the back since it's easier to see from the angle I have.
As far as operation goes, there's plenty on the youtubes about how to use these things. A couple of cautions you should know is as pressure decreases, so does the boiling point as anyone who has lived at altitude will tell you. You don't want to put hot liquids in this machine or really anything much above room temp. The other thing is anything that has a lot of air in it is going to expand under vacuum and this can create a big mess if you aren't careful.
