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cmalberto · 02-13-2016, 01:16 PM

Just ordered a 2017 Coachmen Mirada 35BH - It has a 18cuft Residential Fridge. My reading indicates there is a 1000 watt inverter to drive fridge. I am used to have LP and Electric powered Fridges. I have 2 coach batteries but my question is how long can the coach batteries run the inverter for the fridge. I am more concerned about driving all day without the generator running or multiple days without being connected to shore or generator power.

Any thoughts around this? Thanks in advanced.

**pasdad1** · 02-13-2016, 01:35 PM

While driving, your engine alternator will supply power to the batteries, which are supplying power to the inverter to run the fridge.....so it can do this indefinitely.

While not connected to shore power, you will probably need to run the generator 2 hours in the morning and 2 hours right before "quiet time" begins to keep the batteries charged.

If you want to boondock without power for days in a row, consider getting more batteries and a solar system to recharge those batteries.

Gary RVRoamer · 02-13-2016, 05:53 PM

Lots of variables, so a "crisp" answer isn't possible, but probably 16-24 hours. Other 12v consumption, ambient air temperature, how often/long the fridge door is open, etc. are all major factors.

The fridge probably uses about 1.2-1.4 kilowatt-hours (KWH) daily. That's about 100-120 amp-hours from the batteries, or about 50% of the capacity of a pair of golf cart 6v's. Since you shouldn't use more than about 50% without recharging, that roughly a days worth of use. However, lighting, maybe some tv, and miscellaneous small 12v power draws will cut into that.

Triangle Drifter · 02-13-2016, 06:14 PM

The weakest link is the battery bank. How many usable ah s do you have? Are the batterys a pair of 6V golfcart, 12V group 24s, 12Vgroup 27, maybe even 12V group 31s?

Bets are, the dealer will install the cheapest i.e. a pair of 12V group 24s.

How long the power will last depends on you. Leave the door closed & it will last the longest time. Stand there with the door open sightseeing & the fridge has to work harder restoring cold air killing the battery bank much faster.

Don't rely on the truck to put a big charge into the battery bank as you drive along either. Much depends on the size of the alternator. Also the size of wire & length of run from alternator to trailer batterys makes a difference. The thicker the wire & the shorter the run, the better.

okmunky · 02-13-2016, 06:31 PM

If you plan to dry camp often, you may want to rethink the residential fridge.

Ranger Smith · 02-13-2016, 06:31 PM

I have a residential in my Winnebago and it has a 2800w inverter and 6 agm house batteries.

twinboat · 02-13-2016, 07:06 PM

With the residential refrigerator you want to make sure the dealer installs some decent batteries.

I would call Coachmen and ask what they recommend for batteries. Then make sure the dealer installs them.

Your chassis has a 175 amp, heavy duty alternator, so keeping the batteries charged should not be a problem.

While parked without shore power, a few hours generator time in the morning and at dinner should be all you need to keep the ice cream hard.

If you plan on a lot of boondocking, a battery monitor is a good investment.

cmalberto · 02-13-2016, 07:42 PM

Thanks everyone...you gave me a good idea of what to expect. I don't really plan to dry camp and I do have the Generator when needed to help out the batteries. I guess I was thinking about driving down the road primarily but we do plan to leave the coach plugged in but what if we are away for a week or so and lost power. Things to know...Thanks again.

mojoracing · 02-13-2016, 10:35 PM

The dealer is not the one that installs the batteries. The manufacturer, in this case, Coachman is the one that installs them. If he wants to upgrade them that would be up to him. Do your research and find out what brand, type and number of batteries will work best in your configuration.