Freeze Dryer Maintenance and Care: FAQs, Cleaning Tips, and Troubleshooting Guide

Freeze dryers aren’t exactly cheap, like other kitchen or laboratory equipment. They cost quite a lot, so you want it to last a long time. Extra care when owning a freeze dryer goes a long way, which is why you should put time into proper maintenance.

Ensuring regular maintenance of your freeze dryer allows you to have a machine in tip-top running condition. You don’t have to worry about any failures in the middle of the freeze-drying process, which can ruin your goods. Aside from that, scheduling regular maintenance will also allow you to look for possible signs of damage so that you can remedy them early on. Early prevention and repairs can save you thousands of dollars in repairs done after a late diagnosis.


The Basics: Cleaning your Freeze Dryer 

Always make it a habit to clean your freeze dryer after use. The last thing you want is to contaminate your food or cannabis because of bacteria that developed from dirt or grime that accumulated inside the freeze dryer.

So, how often should you clean a freeze-dryer? While a quick wipe should be enough after use, a deep-down cleansing is ordered once every other week. When you do a deep cleaning of your freeze dryer, you can use the following to make the job easier:


  • Clean Water
  • 91 percent Isopropyl Alcohol
  • Clean towels or microfiber cloths
  • White vinegar or diluted bleach
  • Bottle cleaning brush
  • Toothbrush
  • Spray bottle


Note that if using bleach, it should be diluted to a tablespoon for every gallon of water. You should also not use abrasive chemicals on the plexiglass door, as this can damage the finish.

Before cleaning your freeze-dryer, ensure the machine is off and unplugged. Also, avoid getting any chemicals or touching the heating elements in the tray system to prevent damage.


  1. To begin cleaning your freeze dryer, remove the rubber gasket of the freeze dryer, along with the trays and rack system. Inspect the chamber and condenser for any debris material and remove any.
  2. Spray the door with white vinegar or water-bleach mixture and wipe it thoroughly on both sides. They move to the chamber, clean it using your spray solution, and scrub them with your clean or microfiber cloth. If you encounter any stuck resin, clean it with isopropyl alcohol and scrub it with the toothbrush. After scouring the insides of the chamber, wipe it once more with another clean cloth and water. Get another dry clean cloth, then wipe the interior dry.
  3. Clean the rack and trays with your spray solution and scrub them with a microfiber cloth. Use isopropyl alcohol and microfiber for stubborn stains. Wipe them after with a cloth and clean water, and dry with another dry clean cloth. Conduct another inspection, and make sure the drain line has no debris. Replace the drain line if damaged.
  4. After inspecting, return the rack and trays and replace the rubber gasket, ensuring the seal is flat and secure. If there is moisture inside the chamber, leave the freeze-dryer door open to completely dry and avoid mold growth.  


It's a best practice to leave the door open while the machine is defrosting and/or not in use. Keeping the door closed only invites mold growth if there’s any remaining moisture inside. 


Oil Change  

You can skip this part if you have an oil-free vacuum pump.

Another essential part of freeze-dryer maintenance is changing the oil of the vacuum pump. One full load in a vacuum pump should be good enough for 100 hours of use. Your mileage may vary here; you won’t get as much in some cases, depending on what you freeze dry. As a rule of thumb, if the oil is dark brown or black, it’s time to change it.

It’s best to drain the oil when warm. Draining the pump after the oil has cooled can pose a challenge when getting rid of substances that get sucked into the pump. When the oil is warmer, it’s less dense, so it’s easier to flow things out. You can use a filter to sift for debris and check for quality when draining the oil.


Harvest Right Vacuum Pump OilHarvest Right Oil Filter


It’s essential to keep the vacuum pump clean and without debris. The pumping device needs regular lubrication to ensure that your vacuum pump is able to remove excess water from the freeze dryer. 

Now, if you want one less thing to deal with, and you use your freeze dryer, regularly, an oil-free vacuum pump is a worthy investment to have. 

Proper freeze-dryer maintenance ensures that you get the most mileage from your machine. Maintenance prolongs the life of your freeze dryer and allows you to get the best quality possible with your food. As freeze dryers are commonly used on food, you should prevent possible contamination from bacteria that may develop. Maintenance goes a long way, and it will be the first and last line of defense of your freeze dryer versus permanent damage.  


Frequently Asked Questions 

What should I do if I notice an unusual smell from the freeze dryer?

If you notice any unusual smell coming from your freeze dryer, there’s likely some old food debris or stains left inside it. You can fix this using spray or isopropyl alcohol and scrubbing with a toothbrush.

Can I store the freeze dryer in a cold or humid environment?

Freeze dryers work best in room temperatures of 45 – 80 degrees Fahrenheit. As they emit a lot of heat during the freeze-drying process, they work better in cooler environments and with a lot of ventilation.

How do I troubleshoot common issues with my freeze dryer?

First, you must ensure all connections are firmly in place, including hoses and sensors. These things are the first that cause issues and are often resolved by ensuring they are properly secure. You should also restart the freeze dryer when errors are detected.

Are there any safety precautions I should take while using or maintaining the freeze dryer?

To ensure that your freeze dryer works in ideal scenarios, ensure the room is not humid or too cold. There should be sufficient ventilation also, as freeze dryers can emit a lot of heat. Your freeze dryer should also be on a stable surface to prevent damage. When troubleshooting or conducting maintenance checks, ensure the freeze dryer is unplugged before opening anything.