March 7, 2020

Chest Freezer to Fridge Conversion

Between my book giveaway and kidding, I haven't had a chance to share my progress on our solar pantry project. I left off about a month ago, when I showed you how we adjust our solar panels. The next step was replacing my old energy-guzzling pantry refrigerator with a low-energy DIY chest fridge.

My freezer and new 5-cubic foot chest refrigerator on the back porch. The
7-cubic foot size is more common for this, but this is what I had room for.

There are caveats, criticisms, and a couple of challenges that I'll discuss in just a bit, but first I want to show you how I did it. It was a simple procedure.

These are more energy efficient than uprights because cold sinks.
With a chest, cold doesn't fall out onto the floor when it's opened.

All that's required is a refrigerator thermostat/temperature controller.

This one cost about $55.

It hangs on the wall behind the fridge (the hanger chain was included) and the probe is placed roughly midway in the unit. The knob on the front lets you set and adjust the fridge's internal temperature.

The freezer's electrical cord is plugged into the back of the controller plug, which is plugged into the outlet. That's all there is to it.

In my case, I plugged the controller into a Kill-a-Watt meter because I want to see how much electricity my new appliance is actually using. The meter is what's plugged into the outlet, as you see in the set-up photo below. The power strip is plugged into the house (grid) electricity.

It's upside-down because of the placement of the power
strip. We use that because the outlet is behind the freezer.

The fridge surged to 80 watts when I plugged it in. I used a digital probe thermometer to adjust the setting. Now that it's cold, I'm finding it uses only 0.08 kWh per day—a huge difference from my pantry fridge which uses 2.6 kWh/day! The chest fridge will use less in one month than the old fridge uses in one day.

Caveats? Refrigerator/freezer experts say such a conversion isn't a good idea because a freezer compressor isn't built to operate at refrigerator temperatures. That means appliance longevity may be compromised.

The other problem is condensation inside the unit, since it is operating at temps above freezing. (In a freezer this becomes the ice that needs defrosting.) This is especially true of units which have the compressor in a box that forms a shelf. So the interior must be wiped out regularly.

Criticisms? Bending over to get food items is considered an inconvenience. Some people can't or don't want to bend over, others think it would be too much of a hassle finding things—although I can't say that an upright with shelves is any easier. The thing I'm looking for is always shoved to the back on a different shelf! The trade-off would have to be the desire for considerable savings in electricity and a willingness to develop new habits.

Challenges? For me, it's how to organize it as conveniently as possible. Most people use the milk-crate style file storage boxes. They have straight sides, are stackable. For the 7-cubic foot size chest fridge, they fit nicely, but for my 5-cubic foot model, they are just a tad too big.

The basket is too long to fit the width of the unit,

and too long to fit between the wall and compressor shelf.

The next size smaller milk crate is the 13-inch square. But I'd lose too many inches of storage space to make that a desirable idea.

Width from freezer wall to condenser unit shelf.

My pantry refrigerator is my auxiliary fridge. I use it for storing mostly homegrown foods such as fresh goat milk, eggs, whey, cheese, and garden produce. This chest fridge is going to take its place. I figured out that I can fit nine half-gallon jars of goat milk in the bottom and somehow place the crate on top of that. But how? Here's what Dan helped me come up with.

A stand made from PVC corner molding and PVC glue.

I'm thinking jars of the freshest milk can be cooled on the shelf first, then
moved to the bottom. The crate can hold leftovers, fruits, cheese, & veggies.

I still have some room above that, for which a sliding basket or two would be perfect for things like condiments and salad fixings. Unfortunately, the one basket that came with the unit is too tall if I use the crate.

The basket itself is 6.5-inches tall, but with the hangers it's 8 inches.

A six-inch depth including hangers would be perfect. Unfortunately, I couldn't find them that size. Happily, I found two totes that will do the job.

At only $4 each, how could I go wrong?

Two fit perfectly side by side.

I may look to replace the crate with a tote if I can find the right size. I like that the totes have bottoms, so spillage remains contained and easy to clean up.

Once we get the old fridge out of the pantry, we can start working on phase two of our plan, improving pantry insulation.


Practical Parsimony said...

I could not physically use that. The boxes may interfere with the circulation of air and cooling...??? But, I do admire your ingenuity.

Leigh said...

PP, I can't claim any ingenuity! I just followed directions from others who have done this. I don't think the boxes will interfere any more with air circulation than shelves in a regular fridge do. There are inconsistencies in its internal temp, but I find those in upright refrigerators too; it's always colder at the top under the freezer than on the bottom. One suggestion others have given me is to keep an ice bottle in one of the top containers. The old ice box effect. :)

Judy said...

I'm wondering the same thing as Practical Parsimony is about the boxes interfering with the circulation of the air. I would think places like IKEA would have the baskets and crates that fit your needs.

Leigh said...

Thanks Judy. But is it really circulation of air that I need? Or circulation of cold? There's no fan in the unit either way.

wyomingheart said...

Hi Leigh. Have you noticed any moisture on the side walls? The nice part of those totes is that it will keep the cold inside. I think the remedy for storage shelves is genius! Solving problems on the homestead is mostly about using what you have on hand. Perfect, in my humble opinion! Thanks for sharing.

wyomingheart said...

I forgot to add, that if you do notice moisture, perhaps you could use those dry rid boxes for closets. Just a thought!

Helen said...

I also wonder about air circulation with the 'solid' bins. Drill some holes?

Leigh said...

Wyomingheart, I haven't had it running long enough for condensation to form yet. I'm expecting it, though, because everyone else who has done this has had to deal with it. Moisture absorbers is an idea to try. Other than that, most folks simply wipe it down periodically.

I got the idea to use the storage boxes in place of shelves from someone else too! I agree with using what we have, or at least finding inexpensive substitutes!

Helen, the logic for the concern about air circulation completely escapes me. The solid storage bins I'm using are no different than the crisper and meat drawers in an upright fridge---those are solid as well. Plus, those are tucked away under a solid shelf to make completely enclosed boxes, whereas mine are open with about an inch of space on both sides. I'd have to conclude that a chest fridge has better "air circulation" than an upright.

arta said...

Great job!! We use ours the same way and the condensation is not really a big problem. Yes, some condensations collects at the bottom, but not a lot and not often. Every few weeks, I soak it up with an old towel and we're good to go again. Because we live in a desert, we use our bottom for cold water storage. We pack them in tightly at the bottom and it creates a cold mass that helps keep everything else cool as well. And the stuff we use often, we pack in the bins at the top. You will be surprised at how much more efficient this unit is than a normal fridge :) I am very happy for you!

Leigh said...

Arta, good to hear from you! And thank you! I've been amazed at how little electricity this uses. I plan to keep an ice bottle in one of those bins in the top to help even more. I'm very glad to hear that condensation isn't a huge problem for you. I'm not sure what to expect. I plan to use the bottom of mine for milk, but you've got me thinking I could use the empty spots for cold water storage as well.

Sandi said...

How much did it cost to make?

Leigh said...

Sandi, I bought the freezer unit new, and it was about $200 including tax. The thermostat was $55, so my cost was around $250. If one already had a freezer to convert or bought it used, the cost would be less.

Mama Pea said...

Can't tell you how much I admire your ingenuity and willingness to try "new" and "different" things in the name of energy saving and efficiency. And, oh my, the energy expected to be saved is amazing! Gotta say that I do dislike the idea of a chest type refrigerator though. I know I could make do with it if I had to, but also know that my main chest freezer has baskets (always loaded) that fit all across the top and I'm constantly hefting them aside to get to whatever is stored in the chest underneath . . . and it feels like a hassle. I'd be putting up a terrible fuss if anyone tried to take my kitchen refridge away from me. It's an upright, all-refridgerator Crosley (no freezer) that we've had for close to 25 years with absolutely no problems and we rarely hear the motor running. I don't think they are currently being made so I sure hope I haven't jinxed myself bragging as I have. :o\

Leigh said...

Mama Pea, I have the same problem with my chest freezer, so I'm really hoping to do a better job of organizing the chest fridge. It's smaller though, so hopefully that will help (?)

They still make an upright all-fridge (no freezer) and I considered it but this worked out to be a better bargain. I don't remember what the brand was. Nice your's is still working so well! They're probably not as well made nowadays.

Ed said...

We've got milk crates in our freezer with stuff crammed into the extra space around them. It has been on my list for awhile to someday build my own crates out of 1/4" plywood that fit better and are in more convenient sizes.

Cockeyed Jo said...

Personally, I think it's an ingenious appropriation.

Nancy In Boise said...

Great job! We use baskets too in our 7 CF freezer, great for organizing food. Great idea!

Leigh said...

Ed, finding the perfect organization solution is a huge challenge! In a freezer, plywood boxes in custom sizes sounds ideal. Because of my potential condensation I'm stuck with plastic.

Jo, thanks! I'm especially amazed at how little electricity this fridge uses. I've got it plugged into our solar and it has made little difference in the amount we're drawing from the battery bank.

Nancy, that's an ideal size, I think. The baskets seem to fit better in that size.

Ann said...

I'm pretty happy with my solution for organizing my chest freezer, but not sure how it would work for a chest fridge, because of both moisture and the type of stuff you might store in a fridge. I bought a set (two sets actually) of nylon reusable grocery bags. As much as possible they're color coded so I know that yellow is corn, purple is bell pepper, etc. When I'm looking for something I can just lift out whole bags to get below them. So stuff stays sorted.

Leigh said...

Ann, the nylon bags is a really good idea. I'm not sure either if it would work for the fridge, but I could still use that idea for my freezer!

Chris said...

As long as you have your health, to lift things up and down, then it's a winner, just for the money it will save. Maybe Dan can invent a kind of arm on a hinge, the totes fit in permanently. So whenever you want something underneath, they can be manouvred up and to the side, rather than being physically lifted. I'm thinking of those wooden art boxes, with internal boxes, that lift up and to the side, in the same way. Some fishing tackle boxes, do the same thing. Otherwise, it's great to see your plans, come to fruition after all that initial work!

Leigh said...

Chris, great ideas! I'm just going to have to keep things manageable by what I put where. I'm already coming up with a different scheme for the milk. Still, the savings on electricity and having at least this one little fridge off the grid is a comfort.

Kathy Richards said...

Hi! We’re considering going off the grid, or at least cutting waaaaaay back on our energy usage. How is the freezer to fridge conversion going now after two years?

Leigh said...

Kathy, hello and welcome! It's still in use and definitely something I'm glad we did. Currently, we're getting ready to upgrade the battery bank -> By upgrade, I mean install a new battery bank with more storage capacity. Details at that blog post.

Anonymous said...

Have you noticed any issues with your compressor? We converted ours a couple years ago. We started with a freezer that was probably at the end of its life anyway, bit so far, so good. It does seem to run hotter (although it doesn't need to run as long). We haven't found the different orientation too inconvenient, but there is a bit of condensation in the summer. Any suggestions appreciated!

Leigh said...

Anonymous, we had problems with ours last year and thought it might be the compressor. Dan went to YouTube and searched the model number plus problem and found videos that helped him troubleshoot. What he ended up replacing was the timer, and that took care of the problem.

Seems like the compressor is a common problem with this set-up, although I've seen new freezers that have settings that allow for low 30sF. One of those might help with the condensation too (also a problem!) so that might be an option when you finally need to replace yours.

Crunchbird said...

My freezer conversion worked fine but it suffered from condensation issues. I added a 5V computer fan running from a small USB charger inside and it is now just as dry as my refrigerator. There has to be a way for the inside moist air to be evacuated. Right now I simply use a thin piece of wood to hold the lid open about a quarter of an inch. Hey it works! A better method might be to add a hole in the lid. I may try this but right now it's working perfectly.

Leigh said...

Crunchbird, that's a great idea. So far I haven't had a lot of condensation issues, but it's good to have someone's success story!