Freezer to refrigerator conversion need some information

Re: Freezer to refrigerator conversion need some information

It really depends on the refrigerator vendor... Most small refrigerator/freezes seem to use the same compressor as the large units... Which means that the compressor tend to run at ~110 to 130 watts (warm days, just after it has started, the compressors tend to draw a bit more running power).

On starting, it is not unusual for one to draw 5x starting current.

If you have a "no frost" or self defrosting unit, then there are electric heaters which (typically) appear to draw around 500-600 watts.

So--For a full sized US energy star refrigerator, a good 1,200 to 1,500 watt inverter is about the right size (and leaves a little extra power for lightning/radio/tv etc. around the home).

One person here (Wayne from Nova Scotia Canada) has converted his mid-sized chest freezers to run off a 300 Watt Morning Star TSW 12 volt AC inverter (the Morningstar is rated for 600 watts for 10 minutes). However, to do this he has experimented with using different motor start capacitors, an autowound transformer, and timing relays. The Capacitor change reduces starting surge (or may actually increase surge current, but starts quicker--don't remember). And the relay+autowound transformer is setup to take something like 120 VAC in and output 100 VAC out--This supports more surge current to the motor at a lower voltage--That reduces surge watts on the AC Inverter.

And Wayne's system has been running reliably for years (as I recall, he runs several fridges/freezers from one 300 watt inverter and relays that sequence the AC power between two or three loads), and uses a second inverter to run the rest of his home). Wayne has taken a lot of time and effort to get his system running reliably--plus he does still have utility power if something "goes south" as backup.

The answer is "yes, you may be able to do it", but do you want to do it with a minimum sized AC inverter (and assuming your freezer conversion is amenable to running on the system that Wayne has devised)--Or, would you be better off to buy a good quality 1,200-2,000 watt TSW inverter and have extra power for your rest of the loads in your home.

Also note--Many of the frost free refrigerators these days use electronic defrost timers--When the AC power is cycled (inverter "goes to sleep" in search mode), the defrost timers (typically defrost every 12-24 hours, as I understand) reset to zero and start a new defrost cycle. So, things are getting a bit more difficult with modern appliances to "hack" (there are still many small frost freeze freezers out there--so you probably will not have defrost heater/electronic timer issues).

Your thoughts/needs?

-Bill