Refrigerator-low draw options

[Bluedog225]

Based on this thread,

Microwave for a 1200 watt inverter?

Hey guys, a while ago I built a 1200-watt system for camping. I would like to have a small microwave but I bought a 700 watt one from Walmart and it freakin pulled 1400 watts and tripped the inverter. And my bms is 1200 watts so a bigger inverter doesn't help. Anyone using a small microwave that...

diysolarforum.com

I’m going to order the recommended microwave.

And I ordered the victron 12/1200.

Does anyone have a good suggestion for a “best in class” fridge? Or a ”better” microwave?

Is there such a thing as an “inverter“ fridge?

Thanks

 

[HRTKD]

I would be looking at a DC compressor refrigerator that doesn't require an inverter at all.

 

[ElectricIslander]

There are LG Inverter fridges that don't draw too much, we have a 20 cu ft side by side bottom drawer LG Inverter fridge that draws something like 450 Kwhrs/yr. It typically draws an average of about 30 to 40 watts, has no significant surge and appears to adjust run speed to current need for cooling.

 

[sunsurfer]

The defrost cycle and the heating element near the bottom of a freezer door consume allot. I'm using an upright fridge or freezer(convertable) that does not have a defrost heater or blower fan. Down side is, moisture on the inner walls all the time. It is a Vissani from homedepot, about the size of a large RV fridge.

Vissani 7 cu. ft. Convertible Upright Freezer/Refrigerator in Stainless Steel Look MDUFC7SS - The Home Depot

Bring freshness to your life with the VISSANI 7 cu. ft. upright freezer. The removable shelf will help you to manage your storage flexibly. The convertible function gives you additional choice in managing

www.homedepot.com

 

[DPC]

You price the compressors

Wow I wonder if j should buy a bunch and sell the rest on eBay

Source New type R134a 12V/24V DC power mini DC LBP Compressor on m.alibaba.com

New type R134a 12V/24V DC power mini DC LBP Compressor, You can get more details about from mobile site on m.alibaba.com

m.alibaba.com

 

[Leeds]

In solar-land the "best in class" fridge is a chest freezer run at 38°

 

[Jack Rabbit Off Grid]

I have this one. bet I cold start it of my 400w inverter. Only thing I don’t like is every 24 hours it does a 200w defrost cycle. I wish they made an inverter deep freeze also but they don’t.

20 cu. ft. Top Freezer Refrigerator - LTCS20020W | LG USA

Discover the 20 cu. ft. Top Freezer Refrigerator that features Reversible Door and Premium LED Refrigerator Lights. Shop LTCS20020W from LG USA.

www.lg.com

 

[sunsurfer]

In solar-land the "best in class" fridge is a chest freezer run at 38°

We did that for about a month. I hope I never have to repeat that again.

 

[time2roll]

Microwave is about .9 power factor so about 10% additional apparent watts may be needed. So that 980 watts consumed need 1100 watts available. Good but very close.

Consider a Panasonic "inverter" microwave that reduces power at lower settings instead of cycling the magnetron at full power. This one goes as low as 670 watts on power level 3. If utility or generator power is available then it can use full power.

. Skip to 4:00 time

Sorry, no help on the fridge. Mine is propane and 250 mA.

 

[Bluedog225]

Cool. I misread the other thread. Thanks!

 

[Bluedog225]

We did that for about a month. I hope I never have to repeat that again.

Curious why not?

 

[rodrick]

We did that for about a month. I hope I never have to repeat that again.

What did you not like about a chest refrigerator

 

[pollenface]

I think any modern energy efficient fridge would be fine on a 1200w inverter.

I never see my 265L fridge draw more than 300w when the compressor comes on (don't know how accurate my measuring equipment is though)

 

[Bluedog225]

I’ve not done it. But it seems like it would be an easy hack to cut out the defrost circuit. Fridges and freezers are pretty modular, plug and play components.

 

[sunsurfer]

What did you not like about a chest refrigerator

Its hard to get food in or out. Things end up sideways and on top of each other. Its like one shelf but you have to put stuff on top of each other since there isn't much space. One or two people could make it work. A system of stacking tubs could help. Most of the items end up collecting moisture on the outer surface. Water will collect on the bottom since most freezers don't have a tapered drain at the lowest point. Our drain was about .5 inches up from the bottom.

Our current fridge has moisture on the walls since its a convertible upright and the walls provide the cold surface. We have not had issues with moisture on the containers. I'm not sure why there is a difference.

 

[v_green57]

I’ve not done it. But it seems like it would be an easy hack to cut out the defrost circuit. Fridges and freezers are pretty modular, plug and play components.

Did just that years ago.

The coils frosted over and it wound up using MORE power in the long run because the airflow through them became restricted.

Fridges with auto-defrost are engineered to have it. If you disable it, things become less than optimal.

 

[DPC]

I learn a lot from these threads


Inverter micrwave
I would have never even thought of that

 

[OzSolar]

FWIW: ~1.5 kWh/day for a standard fridge that anyone can buy at thier nearest appliance seller is not a bad deal at all. I've played around with the "total system cost per cubic ft" a few times and the standard Energy Star fridge is often the winner for most applications.

 

[DPC]

I was looking real hard at this fridge at work
( we have a lot of fridges and lunchrooms so we buy a lot of appliances…. Always something new shows up )

It’s just a cheap unit with a small compressor small size and few basic controls
What stood out for me was no indication of a timer for frost free functions
Easy to buy r600a
No internal fans

I thought it might be a good candidate for 12 volt conversation

After reading this thread I’m not so sure there’s an advantage to it

 

[DPC]

Some technical as built details

https://catalog.huayicompressor.es/pdf/huayi_compressor_B60C5BL_R600a_115_60.pdf

Locked rotor currrent is low 6 amps so it’s easy to start as built
6 cc compressor volume

The Danfoss bd50 by the book looks a little small for this
The bd80 is 3 cm compressor

Advantage with inverter is you can set compressor speed
I could adjust it to run 3500 rpm and match the cooling power of the ac unit
I can set it to 2000 rpm and tune it to the unit to run at a 50 percent duty cycle for peak efficiency

Bd80f is rated for the new refrigerant
Technical details on it lead me to think it might be more efficient that the old non flammable types

Flammable however
Now we are back to a refrigeration system that can cause a fire same reason I have turned my nose up to absorption fridges

Thought experiment
Is it worth the trouble to build a fridge
With a really well insulated box myself and fit a chill plate and compressor system all by myself