freezer efficiency

So our danby 5.1 120vAC freezer sits outside in our shed. For about 2 years it was exposed to the elements but covered and was not getting rained on. I recently moved the freezer into the battery room, which has a door and is sealed in a sense. I believe the freezer will perform better in the room than out exposed to every wind gust and fog/mist.

Than I started to think about how the freezer is currently in a room which is 4*C(39*F). The freezer will experience below 0*C(32*F) every now and than. However I started to think about the process of the freezer. Not being well versed in freezer workings. I was wondering if insulating the moter/compressor would help the process. The outside case of the compressor/motor is around 31*C(88*F). Being that heat is part of freezing. The freezer might be more efficient if the motor was hotter? As there is currently no other source of heat for the process.


Just some musings. The internal wiring for the freezer was all 18awg wire! I upgraded part of it to 14awg.

Our kill a watt meter is buggered. The screen doesn't display in a readable way. I would be using that to determine this process. I was thinking of putting a layer of insulation around the compressor. The insulation would be removed when the weather warms up.....

SO what do you think? Worth it?

jordan barton wrote:So our danby 5.1 120vAC freezer sits outside in our shed. For about 2 years it was exposed to the elements but covered and was not getting rained on. I recently moved the freezer into the battery room, which has a door and is sealed in a sense. I believe the freezer will perform better in the room than out exposed to every wind gust and fog/mist.

Than I started to think about how the freezer is currently in a room which is 4*C(39*F). The freezer will experience below 0*C(32*F) every now and than. However I started to think about the process of the freezer. Not being well versed in freezer workings. I was wondering if insulating the moter/compressor would help the process. The outside case of the compressor/motor is around 31*C(88*F). Being that heat is part of freezing. The freezer might be more efficient if the motor was hotter? As there is currently no other source of heat for the process.


Just some musings. The internal wiring for the freezer was all 18awg wire! I upgraded part of it to 14awg.

Our kill a watt meter is buggered. The screen doesn't display in a readable way. I would be using that to determine this process. I was thinking of putting a layer of insulation around the compressor. The insulation would be removed when the weather warms up.....

SO what do you think? Worth it?

hi Jordan, if it's less than 10 years old it probably has the freeze protection built into the compressor. Usually if it's really cold the compressor gives itself a shot of heater to better turn over then the running gives it all the heat it needs. I've had one on a kill a watt outside and it peaks high for about 30 seconds then drops down to operating wattage. I would say you let it be.

Howdy,

I am off grid with micro hydro elec and some solar panals. My freezer is a Kenmore 120 volt. It is outside in a covered breeze way type setting, sides open but protected somewhat from rain etc.  My understanding is that the outside temp will help keep the freezer from to much on/off running. I don't think you want to "insulate" the compressor motor. I keep my freeze temp at 10 below. It has been running like this since the 1990's. The only problem I've had was a bear tipped it over when it was in same shed but on ground level. Moved it to second floor, bear ate 100/150 lbs. of frozen organic grass fed beef.

No, leave the compressor area alone.  If you want ultimate efficiency, insulate the outside of the freezer and maybe the front door ( just look under the freezer to ensure the coils are visible, and not concealed under the outer skin.

Here is a link I think you'll enjoy:
https://ecorenovator.org/forum/showthread.php?t=5408

Also, I enjoy reading the other topics in their  general forum:
https://ecorenovator.org/forum/

Cheers

Moving it inside is going to raise your electrical consumption.   For two reasons.  One is that the ambient temperature is higher, and that means automatically the freezer will need to run a bit more to offset the warmer temperatures.

Secondly, as the heat exchanger that pulls heat out of the freezer compartment dumps the heat, it is dumping it into a room where the heat is not going to escape, raising the temperature more.

I see this myself clearly with my on frig and freezers, which consume less electricity in winter, than they do in summer.

A fridge/freezer in a colder room will consume less electricity than one in a warmer room. The compressor is activated when the temp raises higher than the presets of the thermometer in a freezer. So having a freezer outside in a colder temp area would be more efficient than in an insulated room, because the freezer will turn on the compressor less frequently and for shorter duration of time.

Insulating the motor is a bad idea. The heat generated is from it mechanically spinning, if the motor temp triggers the overheat protection switch (depends on quality of fridge), it will shut off until the motor temp drops. In the winter time it might not be much of a problem, but in the spring/summer, this could result in you losing all your food inside since the motor may shut down, before it has time to reach freezing temps.

Best option:
Buy energy meter on amazon for $10 and test in both places. Keep in mind that contents of freezer also plays a role in how long a freezer will hold it's temp when turn off, which is why some people had water jugs or fill freezer to max. This will keep a freezer cooler for a longer period of time when it's off.

thank you for all the replies. We finally got a new kill a watt unit. I have been monitoring the unit. Right now I am seeing around 0.24kwh per day. This is with the freezer set to -14*C. We turn the freezer on at 8am or so and shut it off at midnight or whenever I go to bed. We sleep with the inverter off :D

Not sure I can get better than 240watts per day. The unit seems to use 50+/- watts when running. The kill a watt doesn't list how long the unit is on for. It would be more power if we left the freezer on for 24hours.

240w / 16hours(roughly) = 15watts an hour. 15w x 24h = 360watts per 24hours(0.360kwh).

One thing the kill a watt doesn't take into account is the need to have the inverter in the on mode. When the inverter is powering something it draws 25w/hour. So that is an inefficiency. However I cannot imagine the inverter is on for very long.

What are some of the other metering devices y'all have?

jordan barton wrote:
240w / 16hours(roughly) = 15watts an hour. 15w x 24h = 360watts per 24hours(0.360kwh).

One thing the kill a watt doesn't take into account is the need to have the inverter in the on mode. When the inverter is powering something it draws 25w/hour. So that is an inefficiency. However I cannot imagine the inverter is on for very long.

Actually, that is not too bad.  25W/h is rather low, lower than my own inverter, and far lower than some of the newer "AllinOne" (AiO) units like MPP and Growatt, which are ~100W/hr.

Since you are shutting the inverter off at night, that suggests to me that your system is quite small.  Could you go into a bit more detail as to what your system specs are, system voltage, solar watts, inverter size, ect?

The reason I ask is because solar has become so cheap recently, I've been advising everyone to upgrade their systems to the point they can leave their systems on 24/7.  That's what I do with both my 24V workshop system, and the 48V cabin system.  My solar arrays are big enough that leaving the inverters on overnight now has become just a trivial load for me that I more or less ignore.

I routinely advise people to shop for panels on Craigslist, with cash and carry purchases, which avoids the obscene shipping charges for all that glass.  Sadly though, looking at the Vancouver Craigslist, I don't see anything for more than 1W/$.  On the other hand, across the boarder in Seattle, I see sellers offering panels in the 2W/$ range.
https://seattle.craigslist.org/skc/ele/d/kent-yingli-255w-ul-listed-solar-panel/7579181093.html
How much trouble would it be for you to cross the border, buy some panels in Washington, then drive back home?  Would you get stopped at customs if you have some panels in the back?