Compressor Refrigerator opt 12v?
Has anyone been using one of these 12v compressor refrigerators? I've heard they are low amp drawing. How are they on the battery?
Forum Discussion
JimK-NY wrote:
I don't doubt your facts either, but some calculations are in order. The larger Nova Kool units use the larger Danfoss compressor set at about 5 amps. If your unit does great and only runs about half time, that adds up to at least 60 AH per day. At this time of year at 37 degrees latitude, 200 watts of solar can only generate a maximum of 50 amp hours per day in full sun, all day with no clouds! (Source: http://www.where-rv-now.com/Notes/Solar/index.php) You are going to come up way short almost everyday and that does not include any other use of electricity.
Our NovaKool 7.5 used 4.2A when cycling as per amp metre. Your calculation of 60AH per day is correct in our experience when the days were warm to hot, nights down to 65F. But if we were camping "at this time of the year", the temps would be much lower and as we tend to shut off our furnace all night and rely on thick quilt for warmth turning furnace on in the morning for short periods and on 55F when we were out in the day, the fridge would hardly even cycle so 20-30AH days for the fridge in the fall and spring would be quite common. Because we dry camp almost 99.5% of the time and choose not to run our genie if possible, having as small an electrical power footprint as possible and still keep comfortable and not discharging the batteries below 50% is always a challenge but it is very doable. If you doubt our camping style, check out the trip reports in our blog.
We orginally started with 190W of solar and 4 AGM batteries and found when the weather got warm to hot, our solar stuggled to keep up. Added another 140W for 330W total and never looked back.
As the 12V compressor fridge was the largest user of electricity from the batteries in our case, I would recomment 2 batteries and 200W of solar just to power the fridge if you wanted to opperate with some independence from a genny or shore power, (A/C excluded).
One thing is for sure, each of our power usage is different from camper to camper. For example, your wifes 30AH /day CPAP usage is more than we would normally consume for all of our daily electricity use minus the fridge.
We have sold the TC and now have a TT with a 6cuft propane/120V fridge. It works fine but if it ever fails, the 9200 NovaKool(9cuft) will fit perfect in the same spot and I already have enough solar and batteries.
Our experience with the 12V compressor fridge has been very different than yours but thanks for an honest evaluation of your situation.
Dave
