Charging house batteries only

[Spirit72]

Have a new rig with the "salesman switch" either all on or all off. It needs to be on for solar to charge, but the fridge and all else is also running. Of course the fridge has a fuse I could disconnect, but no other way to turn it off. Ditto for all else that pulls juice from battery charging. The same is true for charging from the alternator or the generator.

Is there some clever way to isolate the solar/chassis/alternator charging to go to the house battery only? I have read some really fantastic short cut solutions here and am just wondering.

Thanks in advance,
Spirit72

[SafariBen]

The alternator and generator hardly notice the extra load, just hook the solar controller direct to the batteries, with an inline fuse.

[followingsea]

Originally Posted by Spirit72

.... I have read some really fantastic short cut solutions here and am just wondering.

Thanks in advance,
Spirit72

Do nothing! How is that for a short cut?

Solar is suppose to run at least your fridge.

My RV fridges have a off/auto/gas/ or electric. My current residential fridge I turn to the zero setting. When dry camping, I often turn it off when going to bed.

[twinboat]

You don't want to NOT charge the chassis battery from the alternator. The chassis needs a steady voltage supply for all of its components, just like a car.

[StarkNaked]

It sounds like your solar is not wired correctly.

On my Class C, the solar still charges the house batteries when the "salesman switch" is turned to the "store" position. Everything else is off, but solar still charges the batteries.

Do you have a way to confirm that solar is not charging with everything else turned off?

[Mark_K5LXP]

Originally Posted by Spirit72

Is there some clever way to isolate the solar/chassis/alternator charging to go to the house battery only?

You want all the batteries you can charging from shore or alternator when that power is available. Solar on the other hand I would want dedicated to house batteries. Sounds like whoever installed your solar connected it to the switched side of your house batteries. Move that wire to the unswitched side (effectively, directly to the house batteries).

Mark B.
Albuquerque, NM

[Spirit72]

Dear Stark, Twin, Following, & Safari,

How I wish the RV came with a meter (needle or digital) that showed Solar charging, but all I have is 4 stages of idiot lights showing battery strength; 1/4 charged, 1/2...etc.

And yes, the alternator charges house & chassis batteries just fine. It is while boon-parked in wildlife territory that I want to avoid any unnecessary noise from engine and especially the noisy gen. Plus the fridge (etc.) draws enuff that the batteries slowly charge up in the day but run down at night.

The walk-thru person made a point that the batteries would not get charged from solar when the batt switch in the off position. So my solutions are to unplug fuses so the solar goes to the batteries only, or, direct wire the solar to the batteries which is what I need but sounds like some interesting wiring yet to do. I was hoping someone knew of a simple replacement 3-way switch with the 3rd position solar charging only. Better yet, I wish it had been wired to begin with so that Solar would charge even when the switch is in the off position just as Stark said.

Also wish "old tech" paper wiring diagrams with wire colors still came with new vehicles plus exploded diagrams which showed where all the components are with wiring ductwork locations.

Thank you all!
Spirit72

[wolfe10]

Wire solar (through controller) to the house battery (not through wiring that goes through the salesman switch.


Second, if there are things that you DO want to operate with the salesman switch off (refrigerator, for example) wire them separately to the chassis battery (with proper fuse at the battery end).


It is common to have things like propane detector and refrigerator NOT wired through the salesman switch.

[Spirit72]

Dear Mark,

Sounds like you, sir, have the pre-zact answer! Now all I need to do is figure out how to do it. The techs around here charge $180-200/ hr. and I really need to be more familiar with my total rig.

Spirit72

[twinboat]

Could it be that your batteries are old and near the end of their life ?
Battery monitors are pretty cheap and easy to install. That will show you how good your batteries are and how much energy is coming and going.

[Mark_K5LXP]

Originally Posted by Spirit72

I need to do is figure out how to do it. The techs around here charge $180-200/ hr. and I really need to be more familiar with my total rig.

You gotta start somewhere. Best case, look at the back of the solar controller and see where the battery lead goes. You might be able to follow it directly and then surgically reconnect to a proper point. Worst case, you disconnect the wire that's there and run your own that does connect to the right point. Either way you'll know at least how that portion of your wiring was done.

Mark B.
Albuquerque, NM

[THenne1713]

So what is brand/ model of a refrigerator in an RV WITHOUT an OFF switch?

[SJ-Chris]

I'm surprised to hear that you don't have an on/off button/switch for your refrigerator. I've never seen an RV fridge like that (but admittedly I haven't seen dozens of different RV fridges). That would be a horrible design.


It would be super helpful for you to have a battery monitor. Here is an inexpensive one I use. It is very helpful for many things.... $35



https://www.amazon.com/gp/product/B07FGFFHC6



Reasons...
https://www.irv2.com/forums/f54/the-...or-601377.html


Good luck!
Chris

[dvspl]

Originally Posted by Spirit72

Now all I need to do is figure out how to do it. The techs around here charge $180-200/ hr. and I really need to be more familiar with my total rig.

We could all be more helpful if you posted the year/make/model of your rig. As you've probably seen, many have that info in their signature so it's always obvious. My manufacturer (Jayco) will send wiring schematics upon request. Those are very helpful. The "salesman switch" is typically a latching solenoid. Connections made to one side will be disconnected, connections made to the other side are always connected to the battery. If you look at how it's wired, there is possibly a bus or connection stud on the battery side of the solenoid where you could move the positive output of the solar controller.