Perfect refrigerator for insulin storage?!

I have been looking for months for a good refrigerator to store insulin at home, in a way where I have some reasonable certainty that it won’t freeze. I finally decided that the best type was probably a wine chiller, since it as important to expensive wines as it is to insulin that it never freeze. But I could not find a model that I liked and that also got good reviews.

I think I just found the right model: https://www.amazon.com/Westinghouse-WWT120TB-Electric-Adjustable-Thermostat/dp/B00N6RG19I/ !!!

It is made by Westinghouse (in China) and is a thermal electric cooling system (not a compressor). Its cooling range is 46-66, which means I would set up at its minimum temperature at all times. The 46 degree minimal temperature is marginal for storing insulin, so I hope the nominal temperature range will be reasonably true to reality.

The bad thing about thermal electric cooling is that it fluctuates more because it does not have as much power as a compressor. The good thing is that it uses less power, and there is no inductive machine in it, so I think I will be able to power it through an Uninterruptible Power Supply. That is particularly good because I live in power failure country.

I just ordered it on Amazon! I will test its temperature range with a recording thermometer and see how well it does. Then my next step will be to find a temperature alarm that can notify my cell phone if it gets out of range.

I am pleased as punch, and crossing my fingers that it will work well.

I’d steer far clear of that.

First and foremost, storage for 8 wine bottles is horribly inadequate. Secondly, thermoelectric coolers are very poor at temperature regulation even if it says it is “adjustable” I would be willing to bet it only maintains that temp in ideal circumstances and widely fluctuates outside of that range in the real world.

I would not put either my wine or my insulin in a thermoelectric cooler.

1 Like

I hope you are wrong - but you could be right!

Nice thing about small cooler = small amount of power needed -> can use a big UPS to take on 12-hour power failure.
Nice thing about thermal electric --> compressors can’t use UPS (starting spike faults the UPS).
I will double insulate the insulin in styrofoam boxes and put ice packs with it to smooth the curve, and I will put the cooler in the basement, which is steady around 55 most of the year. Perfect for our Wisconsin mice. I am knocking on wood that it will work.

But - I would like it better if the temperature went all the way down to 41:(

Sam, I think you are missing the point. Even if it is not used for insulin, I am sure our favorite Frenchman will find a use for a wine cooler in his basement…
:grinning:

2 Likes

Which is exactly why 8 bottles storage is not enough…

Michel do you have a chest freezer or any other large frozen storage? You’d be better off with a couple bags of ice in a freezer and an inexpensive cooler to keep things cool for 5-7 days than with a crappy thermoelectric cooler and ups to keep things halfway cool for 24 hours

OK, this is a more extensive description of the issue:

Use case
We live in the country, and we are subject to a lot of power failures in all seasons. And, when we leave our two refrigerators for a week or two (which happens several times a year), we are never sure if we are not going to find something a bit frozen when we get home.

So I am looking to remove my son’s insulin from our regular refrigerators, and put it in a separate, dedicated refrigerator, in our underground basement which is nicely cool all year round, if possible on a UPS power supply. It does not need to be big - it just needs to take all the insulin we have.

I am planning on putting all the insulin in styrofoam coolers, pack the styrofoam coolers with soft icepacks, get them to cool in a big, cold refrigerator, then, when it is time, take them to the insulin fridge and leave them there for 3 months at a time.

Every 3 months, I will take out enough insulin for the next three months, put them in our kitchen fridge, and leave the rest of the insulin again in the insulin fridge for the next three months.

I also plan on finding a wireless temperature alarm and leaving it in the insulin fridge so that I can get a remote alarm if anything goes wrong. Hopefully, the thermal inertia of the iced packs and styrofoam boxes will give plenty of lead time before something goes wrong.

Fridge vs compressor-driven wine chiller vs thermal electric wine chiller

Fridge can go down to 33F
Fridge cons
It can freeze
It is subject to power failure
Cannot be put on UPS

Compressor-driven wine chiller can (nominally) go down to 40 or 41F
Compressor-driven wine chiller cons
It may freeze but unlikely
It is subject to power failure
Cannot be put on UPS

Thermal electric wine chiller can go down to 46F, can be put on UPS, cannot freeze
Thermal electric wine chiller cons
It is subject to power failure if very long (beyond UPS)
Its lowest temperature is marginal for insulin (insulin should be kept at 46 or below, which is the lowest temperature you can use a good thermal electric wine chiller)

What are better options than what I am considering and why?

I have a “Dometic WAECO CF-035AC110 Coolmatic 33 QT AC/DC with Touch Control Refrigerator and Freezer” in my camper van. It’s pretty expensive (and does have a compressor) but it runs on either AC or DC. Seems to hold temps within a few degrees tolerance. It weighs about 40 pounds empty but has two good handles and can be moved around. There are a wide variety of similar fridges sold for the RV market. I understand there are some that will run on AC, DC or propane. 33 Quart is too small for wine but they make bigger ones.

Maybe get something similar designed for the RV market and use DC (car battery) in a power failure? This particular fridge draws 45 watts, which can be compared to the capacity of your backup power supply. I’ve run mine on medium capacity golf cart batteries in my van but only for 1-2 days at a time.

1 Like

So John58 has offered a very good approach, i.e. a 12 volt refrigerator and build yourself a golf battery UPS. This will work and would be a nice approach for short and long (up to a couple of days) power outages, although not inexpensive.

Do you have so much insulin on hand that just having a logging thermometer wouldn’t be enough? Since insulin is pretty robust, and using a logging thermometer would help you with knowing that it was stored for x time outside of ideal storage temperatures.

Also, if your power outages aren’t prolonged, it seems that the insulin might not get that warm before the power comes back on and gets back into a more ideal storage temp.

Finally, you mention that your refrigerator cannot be powered by a UPS, that is sort of true, but if you built your own golf cart battery large UPS and used an inverter, you could power that refrigerator for quite some time.

Just a thought.

I just recently bought a garage refrigerator because the insulin was taking up too much space. I also put a sensor in it to monitor and alert me if there were any issues.

The large spike was a test and will alert me if it goes outside the temp range or loses power.

1 Like

What sensor did you pick?

Love the graph. Also, if you want to prevent freezing, you could add one of these to the system.

https://www.amazon.com/dp/B0002EAL58/ref=wl_it_dp_o_pC_S_ttl?_encoding=UTF8&colid=2POLGS3SL7SSZ&coliid=I3OIDR3EAYZRUG

3 Likes

This one I got here. There are many others though.

2 Likes

@Michel, would recommend the purchase of a generator to address your fundamental problem of power failures in all seasons. Even a small generator that you can perhaps hook certain mission critical appliances to, such as the storage of medications, and wine. (Disclosure: I used to work at one of the most reliable utilities in the country)

2 Likes

A post was split to a new topic: “Expired” insulin experiement

OK - so @Chris was right :slight_smile: I returned the thermal electric cooler, and purchased, instead, a compressor-driven cooler, that has a hard stop at 39F.

I also purchased Chris’ Johnson Controls temperature controller. to make sure that it won’t freeze, and a logging thermometer to figure out what the temp curve looks like. I don’t have enough data to share yet, but I am rather pleased so far.

I loaded the thing with a bunch of large plastic water gallons, so as to increase the thermal inertia fo the system to survive a power-down event, and stored the insulin into thermally insulated bags with cooling pads in them as a precaution.

Now, for my next question. I am interested in setting up remote monitoring and alarming, as @Bradford did.

What is your experience with different home automation systems, in terms of reliability and cost? Any recommendations?

Really, it just depends on how much time you want to invest in it. You could do custom raspberry pi systems and make everything yourself–or purchase a commercial system with little set-up time. You could use SmartThings so you can use devices that aren’t just proprietary to Samsung. You can use custom coding, or off the self sensors. Whatever system you use, you will need a hub to connect to your router. These can run as little as $15, but probably average around $75-$99. It really depends on what you want. If you are just looking for this one specific use–then a wifi data logger would be sufficient.

1 Like

@Bradford, I am interested in a commercial system – but my need is limited so far as you can see. What is your recommendation on brand/ technology/ hub?? There is some bad press right now on SmartThings’s unreliable system issues.

Maybe you are right – I should go to a straight datalogger if the system integration is still a pb.

You are correct, there used to be some reliability issues with SmartThings, but an update to the firmware some time ago has since fixed the issues. I, personally, haven’t found any issues in regards to reliability. I personally use https://www.filesthrutheair.com, but there are others that will likely be just as good.

1 Like