I recently installed a residential refrigerator in my 2000 U320. We dry camp two days a year. Will the three 8D house batteries and the three solar panels run the refrigerator those two days? I could also switch the generator to auto. I plan to plug the refrigerator I
into the inverter plug in behind the refrigerator. Thanks
John
Hi, the short answer is -yes.
Qualifying ; as long as it is not a sub zero refrigerator freezer, you have 3-8 D batteries that are fully charged when you start, your solar panels are at least 75 watts each (estimated calculation) and you dont run the microwave for over 30 minutes a day, you dont have medical equipment and normal tv etc.. and auto start... should be no issue
I have no issue with my setup and three batteries and no solar lasting all day. I do run the genset and charge up before bed and again in the morning to make coffee too. If I had solar I probably would not have to do that but I do not have it on this coach.
Yes. That's the short answer as I know it. We just installed a humongous (17.? cf Samsung) in our coach. We have 3 8D house batteries and 450 watts of solar on the roof. The fridge holds it's temps well at night and with Jeff running a CPAP all night we are still good in the morning. We would not need to run the gen long to bring us to a full charge before retiring except that I spend time at night watching TV (also humongous, thanks to Gary Omel, who made me covet his TV and led me down the path to hedonistic HDTV viewing). We are generally good in the morning until the sun comes up ... unless I want to use the elec frying pan or microwave for longer than a minute. We recently spent about 10 days boon docking and had no problems at all. When we DO run the gen, we quickly turn on the ice maker and refill the ice bin. That feature DOES take a good bit of juice, so we are careful about turning it off.
if the batteries have 660 amp hours in actual capacity then 50% discharge is -330 amp hours.
Depending on the other loads the refer alone probably should go two days with no gen run and the panels additional 10 amps per hour if the sun is out.
Baking a turkey in the microwave on the inverter will go past the capacity I would think.
My new 19 cu ft Samsung says the it uses about 400 KW/year without the ice maker in a residential application. That is 1096 watts per day on average. At 12 volts that is about 92 amps per day or 3.8 amps per hour. The refrigerator spec says that the maximum current draw at 120 volts is 6 amps or about 60 amps out of yout batteries throught the inverter. This load is startup loads at fast cool and with an ice maker according to Samsung. The refrigerator doesn't run all the time and certainly is not in start up mode very often. All of the other inverter inefficiencies and motorhome installation adjustments means that all of these numbers will be higher.
So figure it uses 120 amp-hrs in a day. With lighting, TV, heating and all of the other loads I would plan on using the generator. Getting 10 amps/hr for 10 hrs a day would go a long way to making it through a day w/o a generator run. Maybe every other day. I think I did the math correctly.
Makes me want to look at solar more closely.
Roger
we do not have a fancy big fridge as we do not need one for 2 people and rarely watch tv so our 700 amps solar and 3 8d lifelines (755 amph) meant that our gen was never run while in Q for 5 days and on roadside for time too!!!!
That investment is paying itself back all the time and we do use the micro, lights etc constantly.
JohnH