Can/Should I modify my Sundanzer freezer to run at a colder temperature.

wrdaigle

OK, so I'm one of the suckers who fell for the false advertising associated with the Sundanzer freezers. The numbers they advertise are very appealing, but you gotta read the fine print. The advertised numbers are for an internal temperature of 10F, not 0F. In fact, my freezer doesn't actually get down to 0F. Sundanzer is not the only company using this stategy. Many DC and propane freezer manufacturers use 10F as the baseline. The problem is, 10F isn't cold enough for long term meat storage. If you have your doubts, check out Question-Best-Freezer-Temperature.

I have actually had luck storing elk meat at 10F for up to a year, but elk is VERY lean so it stores extremely well. The bit of elk that I mixed up with pork for sausages always got consumed within a few months. But, now I have a pig that will be ready to butcher in a couple of months and, well...I can't eat a whole pig in 3 months. That's just not an option. I can potential store the bulk of it at a friend's place that has some room in a conventional freezer (for a small bacon fee), but I would really like to fill my own freezer with it if possible (I have to run the freezer anyway, and I hate to run it empty).

So, I got to wondering if I might be able to modify my freezer so it runs at a colder temperature. If I crank it all the way down, it will run at about 6-7F , but I would really like to push it a little lower. Right now, it comes on about every 140 min and runs for 30 minutes. At this rate, it uses less than 400wh/day, and I can justify bumping that up a bit if I can maintain a colder temperature. It seems like it should be relatively simple to modify the thermostat so it runs a little longer and maintains a colder temperature. If I can't modify the existing thermostat, maybe I could get another one or build my own using an Arduino based thermostat. I have been working on a Arduino-based monitor for my renewable energy system. I could probably even use the same unit to cycle the freezer compressor on and off.

Any thoughts? Anyone have any experience tinkering with these DC compressors like the one on the SunDanzer? Should I worry about damaging my compressor if I run it colder or for longer periods? My warranty is up, so I'm not too concerned about that.

icarus

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

Have you considered adding more insulation to the cabinet?

Tony

wrdaigle

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

Yeah. But that will only decrease the run time... not the temperature.

icarus

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

You are right, but decreasing the run time is an advantge. I cannot speak to the compressor issue and making it colder, but I wouldn't think it should hurt it. Adding insulation, running it coled, making the run time net/net he same sounds like a win to me.

Tony

waynefromnscanada

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

OUCH! I looked at these units years ago and would have purchased, but couldn't afford the price.
You might be able to modify the thermostat, but I don't know, as have never seen the ones used on those freezers, nor can I comment on running the compressor longer and the possibility of hurting it doing so. However, even to crank it down as low as it will go would be a help, and most certainly shouldn't hurt the compressor any more than running it in hot weather, which would also make it run longer, not to mention when you hand it the pig to freeze. Even if it does quit, the better, high efficiency 120 volt normal household freezers are becoming extremely good on power usage compared to only a few years ago, so there would be no need to pay the very high price for another Sundanzer. "Regular" household freezers have come a very long way in the last few years.

Ralph Day

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

Perhaps sell the Sundanzer on Ebay and head to Sears for a 120vac unit?

Ralph

waynefromnscanada

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

Ralph Day wrote: »

Perhaps sell the Sundanzer on Ebay and head to Sears for a 120vac unit?

Ralph

My thoughts as well. There are definitely some very good "off the shelf" alternatives to the Sundanzer now available, and at a fraction of the cost.
Things have changed, and Sundanzer has a lot of work to do if they want to stay in business.

wrdaigle

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

A quick google search illustrated that Sundanzer has already tackled this issue:

SunDanzer-Ice-Cream-Thermostat.

It looks like this optional thermostat will give the freezer the flexibility to run down to -10F. Sounds great to me. I am going to put one on order. Once I get it installed, I will let everyone know what performance looks like at a couple of different temps.

techntrek

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

If you do convert your existing freezer, it shouldn't be any different than the fridge-to-freezer mods done before. Bypass the existing thermostat and either add a new thermostat in its place or on the power input.

Edit: I left the thread open a few minutes before replying, I see you've solved your problem!

vtmaps

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

wrdaigle wrote: »

A quick google search illustrated that Sundanzer has already tackled this issue:

THANK YOU SO MUCH FOR THAT INFO! What a great forum this is!

BTW, I learned something interesting about the Sundanzer a couple of years ago. The user manual for my freezer gave an ambient temperature range of 50° - 100° F. I had hoped to put my freezer in an unheated outbuilding and take advantage of Vermont's low winter temperatures. I called customer service to ask about this and they told me that the thermostat is NOT in the food compartment. If the ambient temperature was too near the desired operating temperature (in my case 0° F) the unit would not work properly.

I put the freezer in my shop which I keep above freezing (with woodstove) in the winter. In the winter I would get operating temperatures very near 0° F. In the summer, I couldn't get the temp much below 8° F.

Because of this thread, I just went online and discovered that the user manual has been changed since I bought my unit.
From the current manual:

As the ambient temperature changes from summer to winter, it may be necessary to adjust the thermostat to achieve the proper internal temperature setting. If the room/ambient temperature approaches the appliance’s internal operating temperature, the appliance will not function as it should. The appliance will tend to run colder during these conditions and it may be necessary to turn the thermostat to a warmer setting

--vtMaps

wrdaigle

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

In the long run, I plan to build a root cellar in my crawl space. Temps down there run 45-50F all year round, so it should be a perfect place to maintain a nice cold freezer.

fridgeguy

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

SunDanzer sells a colder version of the freezer thermostat. Just give them a call.

fridgeguy

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

The inverter adds to the energy consumption and reduces the reliability of keeping food cold. If you have a large PV system and already have the house wired for AC on a large inverter that is on all the time, then a Sear unit is a reasonable alternative. The benefit of the SunDanzer models is their ability to run directly from low voltage DC.

fridgeguy

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

Don't add insulation! The condenser is in the skin of the unit.

techntrek

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

That's exactly what I see with the fridge in my garage. I have to turn it down in summer and ironically up in winter.

wrdaigle

Re: Can/Should I modify my Sundanzer freezer to run at a colder temperature.

I wrote to Sundanzer and they are going to send me an ice cream thermostat free of charge. So, kudos to them!