Three years ago I reviewed Harvest Right’s Freeze Dryer (Part 1, Part 2, and Part 3). Since then, Harvest Right has updated their freeze dryer with many improvements and new features. SurvivalBlog felt is was time to re-visit this subject and update the review based upon these new and improved features. We’ll also include many of the operating tips that we have learned along the way. We’ve been running the new model of the freeze dryer (FD) for almost a year now, right along side the old model. It made the comparison very easy on the new features.
Harvest Right has obviously been responsive to their user base. They’ve listened to the issues, made improvements that the users have suggested, and incorporated many of their customer’s suggestions into the redesigned FD. The original model that we reviewed had a matte black finish and looked like an industrial machine. While it sat on my kitchen counter for most of a year while we profiled it, it was ugly. It also stood out like a sore thumb with every guest to our house immediately attracted to it.
The new model has come along ways towards the professional fit and finish of the FD. This model was in stainless steel, and their improvements were quite noticeable. While still the same basic size and shape, the clear door now featured nice rounded edges, which contribute to an overall friendlier feel of the machine. The drain no longer sneaks out between the counter top and side panels getting squished in the process. Instead, the drain extension as a nifty cutout that makes it much cleaner. My preference would have been to have the drain mounted in the lower back corner of the machine, as the current one is just loosely laying there. However, the cutout is an okay compromise.
The Controller Interface
The controller on the old FD was certainly a weakness. Its monochrome blue LCD was difficult to read and had a significant flicker to it. It was also combined with two control knobs sticking out of the side of the machine. While I’ve been careful with mine, it didn’t take much investigation to know that this was a weak point in the design. As heavy as the machine is, these fragile knobs would be a break point.
The new models use a touch screen LCD instead. The bright contrasting colors make it easier to read, and there is no worry about snapping knobs off. I did notice that there were times when the response of the LCD touch seemed sluggish, often causing me to repeat touch commands, but it’s easy to recover. This new controller is definitely easier to use. As a bonus, as long as the machine doesn’t lose power in the middle of a cycle, it remembers what you were doing. If you have to short cycle it because you set something wrong, it will remember where it was supposed to be.
One of the issues in the older model is that there was much less control over the food tray heaters, and they tended to raise the temperature of the food to well over 100 degrees by the time the cycle was finished. The new controller seems to regulate this temperature much better, so the food never gets to the point where nutrients are being destroyed due to temperature.
There is some limited programmability available through the front panel. The old unit had the dials on the side that you had to set with every batch. This new unit is programmed through the touch panel and it will remember these settings as long as it doesn’t lose power. We’ve noticed that a batch of eggs (eight dozen large eggs at a time) or a gallon of milk requires a longer freeze time than the unit’s default settings. Sometimes food can fool the unit by seeming to be done when it’s not.
If you know this in advance (because the last batch required more drying time), you can simply program the extra time at the beginning of the run. This works well, because we tend to run several batches of the same foods serially. It’s nice not having to reprogram the unit when you know it requires the same parameters as the last run.
There is a USB port built into the control board that is accessible on the side of the machine. Upgrades to the machine are possible using this port. This ensures that your machine can always have the latest software utilizing the best control algorithms to produce the best product.
Remembers Where You Left Off
Every once in a while we have a major “oops”. We discover the breaker has flipped because we had too much plugged into it. I have also mistakenly shut the unit off by pressing the control buttons too much too often. Then there are the times when you get the unit started and it can’t finish because something has gone wrong and you have to start over. Now what? The majority of these “oops” have been due to human error. Yet, as long as the unit hasn’t lost power, it remembers that it got short cycled and can generally pick right back up where it left off.
Occasionally, it knows that something went wrong and it can’t figure out where it should be, but it’s smart enough to figure out that a full cycle doesn’t need to be performed in order to finish. If this is the case, it will start counting cycles and knock off time as it realizes that there isn’t as much moisture in the food as it originally thought.
Larger Vacuum Hose
The unit I recently tested had a much larger vacuum hose connecting the vacuum chamber to the vacuum pump. This has both good and bad connotations though. We’ll talk about the bad in the next section, but the good part is that the larger hose allows the unit to finish the batches faster. I noticed about a 20% improvement in finishing times compared to the old model. There are many other changes to the unit though, so it’s difficult to know if this improvement is due solely to the larger vacuum hose or if it has any effect at all. For now, I’m assuming that it does.
Last time, I tested the bottom-of-the-line no-frills black unit. This time, I tested the stainless steel unit. The stainless is a sweet option. Just like every other stainless steel appliance, it does show fingerprints, but it is easily wiped down and cleaned. If you have a particularly messy batch of food that gets run through it, you can simply wipe it out with a wet rag.
If you spilled oil, a hot soapy rag makes cleanup a breeze. It is still difficult to clean the vacuum line port and drain port, but you only do that once before you figure out never to try that food again. (Reference the “butter” story in the original article.) The simple exterior makes it easy to clean by simply wiping it down with a wet rag. Because we live in a dusty environment, we do have to remove the side vent panels and vacuum the inside out about once every two months though.
Solid Engineering, Good Construction
This is close to industrial quality in its build. Except for the control panel, it is simple, sturdy, and reliable. The unit is not sturdy enough to survive a drop off the counter very well, but it’s heavy enough that you are not likely to push it around much. It stays put when you set it up and doesn’t move around as you work with it, opening the door or loading/unloading trays.
Less Annoying Announcement Beep
One of the most annoying features of the original machine was the piezoelectric buzzer that sounded when the unit had finished its cycle. While it was loud and could easily notify you when the unit was in the garage, while you were in the kitchen it had its drawbacks. The finish time of the machine never seems to coincide to a convenient time for me. While the machine would hold the food in a frozen, dried state upon finishing the process, that buzzer would sound every few minutes. That’s fine when it’s two o’clock in the afternoon, but two in the morning was quite annoying. You couldn’t ignore it either, because it was too loud and drove the dogs crazy.
We eventually resorted to checking the finish time right before bed and extending the time so the buzzer would go off after we arose in the morning. The new machine has a much more palatable chime when it finishes. I have been able to sleep through it, though the dog can’t. Of course, on the flip side, you may not hear it until you are in the vicinity of the unit. But since the unit holds the food in a frozen state, it’s generally okay.
There are some annoying things with the freeze dryer. None of them are show stoppers, but if you are not prepared for it, you will get frustrated.
Defrosting – Water Leaking Out The Front
When the unit is running, the water drawn out of the food is re-frozen around the sides of the vacuum chamber. After each run, it must go through a defrost cycle to allow the water to melt off. However, as the ice melts, it tends to slide to the bottom and in an occasional extreme case the drain can get plugged. Because it is ice, it is self resolving. But without the vacuum drawing the door closed, the seal is insufficient to keep the backed up water from leaking out the front. On about 90% of the defrost cycles, there is a tiny dribble of water that runs down the front of the unit. On one or two batches a month, there is significant water that escapes until the drain clears up.
Harvest Right’s fix is to place a significant tilt in the unit so that water runs more naturally towards the back of the unit to drain. The more tilt you have, the more likely the drain clears itself before water runs out the front. You can significantly reduce leaking by following that advice. However, you also severely limit how much liquid you can place in the trays. To tilt it enough to drop the leak rate to less than 99% you nearly halve the volume of liquid food the unit is capable of. Each tray can normally hold a full quart of liquid, but raising the front of the unit one inch means that each tray will only hold a pint. Solid foods are not an issue, but milk and eggs are.
Our fix has been to keep a towel laid down under the opening during the defrost cycle or during loading liquid foods. It’s easy, cheap insurance against water damage and makes for an easy cleanup.
The pump is not purpose designed as a food dehydration vacuum pump. It is actually an automotive air conditioning service pump. This means that while it works well for pulling a vacuum, there are some significant issues that must be dealt with when using it in a freeze dryer.
Care of the Pump
This pump is designed to pull a hard vacuum. It is not designed to process a significant amount of moisture. As a result, even though the vacuum chamber and freezer section are relatively maintenance free, the vacuum pump is not. You will have to mess with the pump on every batch. Remember that this is an “oil” pump,, so it will be messy. Just like you can’t deep fry on your stove top without getting oil on stuff next to the fry pan, you won’t be able to perform maintenance on this pump without getting some oil on the pump, you, and the counter or table on which the machine is sitting.
The simplest maintenance is to just drain off a bit of liquid from the pump while it is cool. This will drain off any water that has accumulated in the pump. Then replace the portion you drained off with fresh oil through the top. There are a couple of caveats though:
- Only replace the volume of oil you drained off, not the volume of water. Replacing the entire volume you drain off will cause too much oil in the unit.
- Always check the volume of oil and make sure it is slightly lower than the recommended amount. Because the system shuts the pump off abruptly, there is a tendency for the cartridge to suck up a small amount of oil, making it seem like there is less than what really is there. Too much oil is bad for you. It gets really messy.
We always perform this maintenance immediately after loading the machine, while the freeze cycle is running. This makes sure that the pump is cooled off and the water and oil have separated.
Because of the simplicity of the single chamber design, more moisture is pulled through the pump than what it is designed for. For this reason, you must perform that simple drain step mentioned above every time you use it. Failure to do that means that you will contaminate the oil beyond repair, and you will have to change the entire oil out prematurely.
Some foods also have a tendency to “outgas” particles. Foods that contain significant amounts of chlorophyll will turn your oil green and fill the pump up with gunk. You must change the oil out before it starts to accumulate inside the pump, or you will end up having to disassemble the pump and scrub it out with a toothbrush.
Changing the oil is a messy job. To change it properly, you must follow Harvest Right’s instructions, which involve running the oil through while the unit is running. This does result in oil spray, and you will get it on you. You can get away with not following these instructions a few times if you don’t have heavily contaminated oil or built up gunk in the oil chamber, but you will eventually have to do it. If the unit is sitting in your house, you will be faced with the dilemma of removing the pump and physically bringing it to a place where the mess doesn’t matter or cleaning the mess up afterwards. No matter what anyone tells you, it’s messy.
Short Cycles Of Most Foods By Default
The unit, as delivered, has a tendency to short cycle most foods. It does give you the option to run it for a couple more hours at the end of the cycle without causing any issues. But when it does this every time, you begin to wonder why you can’t program a default mode that increases the finishing time. This isn’t a huge issue, but it is annoying. If you are running a series of batches and you know ahead of time how much more dry time is needed, you can start the unit with that information. However, it’s a trial and error process.
Lack of Tray Storage
We store the empty trays on top of the unit, but they do not stack nicely. Every once in a while, there is a cascading crash as one or more trays falls off the unit to the floor. No damage is done. Still, when it happens at one in the morning, it is jolting. It would be nice if the unit had some sort of storage capability, even as a add on, for empty trays. I’ll probably end up making one out of stainless steel wire.
No Easy Way To Clean Drain
As I mentioned before, there is no easy way to clean the drain in the unit. If you have an accident, you are stuck running buckets of water while you try to clean up the drain or completely disassemble the drain. This isn’t convenient, as you have to work around the freezer unit, which has fragile fins on it. Accidents of this type are not common, but they do happen.
The freezer motor is no louder than a normal refrigerator, but the vacuum pump is annoyingly loud. The frequency of noise generated by the pump is right in the middle of the voice spectrum. So, for those of us who are normally hard of hearing, it becomes nearly impossible to carry on a conversation without raising your voice. This is okay if the unit is running in your garage, but it’s not okay if in your house. Even with the unit behind a closed door in the laundry room, it makes considerable noise.
We have started trying to time the running of the unit so that it is not running when we have company.
No question about it. You will notice an increase in your power usage. I don’t think it is unreasonable to expect a $30 to $40 increase in your bill during normal usage. Depending on how much you pay for electricity, you could see more or less of an increase. If we keep the machine running non-stop for the month, that amount increases to about $60. That may seem like alot, but when you consider how expensive ready-made freeze dried foods are, it is a drop in the bucket. You will spend about $50 more a month and produce many hundred dollars of food in the process. I’ll talk about the actual numbers we saw tomorrow.
In Part 2, we will talk about the “Ugly” aspects of this machine. The “ugly” are those things that can make you really hate the machine. Then, because we don’t want to end the series on a negative note, we’ll talk about “The Bold and the Beautiful” – those things that make you really love the machine in spite of the operating drawbacks. We’ll also include some pictures of actual product