Solar & 12v Fridge

[FL-Joe]

We have been in our 2022 Salem 270 for a couple weeks now. The panel shows the single house battery dipping down to 11v or so overnight but within an hour or so after the sun rises it is back to 13.6v and fully charged.

My question is while we are camped here in FL and plugged in to 30 amp service is the rooftop solar and house battery running the fridge or is the shore power? If the shore power is running the fridge then why is my new battery discharging at all?

[Aussieguy]

both
you can have more than one charger source plugged into a battery.

BUT .... did the battery go down to 11v while on shore power at night ?
unless you are a big power hog the shore power should have been more than enough to keep the battery charged.

Make sure you battery disconnect is not set to disconnect the battery from shorepower


the solar should/will/maybe be wired to always be connected to battery.
or it will have it's own disconnect switch


what panel size have you got?
100w will be just enough to keep things up
200w a lot better
the more the merrier

----------------------------------------------------------------------
if you intend to do a lot of off grid boondocking camping...
a battery upgrade would be worth a look into
either a CG2 lead acid or Lifepo4 battery

[tomkatb]

Learn to read a voltmeter. Takes time.

The 11 volt reading indicates you have over discharged the battery. This damages the battery. You can destroy a battery this way easily in a year.

The 13x reading when the sun comes up indicates something is charging your battery. Nothing else. Batteries are 0 to 12.6 volts when not charging.

Testing the voltage of a battery requires not charging it an hour or more before you test it. They have a residual charge. Cannot really test them with the solar on.

A 100 watt solar panel on a good day will add 25 amps to your battery.

Most days you will use more than 100 amps per day without the furnace. Your battery cannot provide more than 50 amps. Likely less. The free battery from the dealer is often less.

With a compressor fridge you are expected to plug in daily.

If you plan on boondocking much you need more battery capacity, a battery monitor, generator and more solar.

[Beachbourbon]

Should be shore power or propane running the fridge, not the battery. When boondock ing we run propane, when we have 30 amp shore, we run that. I don’t even check the battery when on shore, no need to since it does nothing but charge overnight. Boondocks with a generator is different. No overnight charging since the generator can’t run at night (same with solar) so run generator in the morning to charge, but the fridge is irrelevant since it works on propane

[BehindBars]

Originally Posted by Beachbourbon

Should be shore power or propane running the fridge, not the battery. When boondock ing we run propane, when we have 30 amp shore, we run that. I don’t even check the battery when on shore, no need to since it does nothing but charge overnight. Boondocks with a generator is different. No overnight charging since the generator can’t run at night (same with solar) so run generator in the morning to charge, but the fridge is irrelevant since it works on propane

Thread title says 12v Fridge. Propane may work for you but it is very likely the OP does not have the option of running the refrigerator on propane.

[Beachbourbon]

Originally Posted by BehindBars

Thread title says 12v Fridge. Propane may work for you but it is very likely the OP does not have the option of running the refrigerator on propane.

The Salem 270 shows a normal RV fridge and 40lbs of propane …besides, what 27 ft unit doesn’t have a fridge that runs shore power and/or propane? That’s just ridiculous.

[bikendan]

The OP's full model number is a Salem FSX 270RTKX, not just 270.
Beachbourbon, the FR webpage for this model, clearly states a 12v only fridge:

"Dual Swinging 12V Refrigerator for Easy Access on Either Side"
https://forestriverinc.com/rvs/salem-fsx/270RTK/6738

Where did you get that it came with a 2-way fridge?
The 12v only fridge has been the standard for all different sizes of RVs since the Pandemic started. 2-way RV fridges are now an extra cost option, on some RVs.

Sent from my SM-G781U using Forest River Forums mobile app

[chriscowles]

Originally Posted by FL-Joe

...
My question is while we are camped here in FL and plugged in to 30 amp service is the rooftop solar and house battery running the fridge or is the shore power? If the shore power is running the fridge then why is my new battery discharging at all?

FL-Joe, the 12V converter in the power center should be able to supply adequate voltage and current. It may be a POS but it should be at least marginally adequate based on it's label.

You've described your long history as a full-timer so I assume the converter breaker is on. I suspect that you're not getting enough voltage at the 12V compressor connections due to inadequate wire size, excess length, or poor connections. If the OEM converter is marginal (probably), it's entirely inadequate when handicapped with bad wiring.

Even with wire of appropriate gauge and length, with perfect connections, OEM electrical systems are the minimum they can get away with. The dealer-supplied battery may be less than that.

Like others, I recommend a battery upgrade and more solar panels. I have and like LFP batteries but Pb may be totally adequate for your needs. Don't do anything like that until you've checked voltages as described earlier. You may need to optimize the refrigerator circuit wiring.

[FL-Joe]

Should have made myself clearer. This new unit has a 12v fridge, not a residential fridge, nor a RV fridge. The OEM solar panel and monitor is dedicated to the fridge only, according to the dealership.

I just wasn’t clear on why the panel showed a couple volt drop at night. Maybe it is displaying something different.

Just hoping someone with same setup in a Salem 32’ would know.

[lazyjj]

Originally Posted by Beachbourbon

The Salem 270 shows a normal RV fridge and 40lbs of propane …besides, what 27 ft unit doesn’t have a fridge that runs shore power and/or propane? That’s just ridiculous.

There are numerous rigs with 12V electric only fridges these days. We own a 34 foot 5vr with the 12v electric only fridge and love it. Not a boon-docker, did enough of that in the military, so not having the propane option for fridge is no issue for us and the 12V compressor models cool faster and better.

[PhilFromMaine]

Originally Posted by FL-Joe

We have been in our 2022 Salem 270 for a couple weeks now. The panel shows the single house battery dipping down to 11v or so overnight but within an hour or so after the sun rises it is back to 13.6v and fully charged.

My question is while we are camped here in FL and plugged in to 30 amp service is the rooftop solar and house battery running the fridge or is the shore power? If the shore power is running the fridge then why is my new battery discharging at all?

Like Aussie said, the answer is all of the above if they are functioning properly. To be precise, only the solar and converter are producing power, the battery is only for storage of said power. Your converter will be the main source of power at probably around up to 50-55 amps. It should function 24-7.

If you are waking up to a depleted battery, then there is an issue with your converter. Make sure the breaker is flipped on. If it is on, I would test your converter output.

[FL-Joe]

Originally Posted by Beachbourbon

The Salem 270 shows a normal RV fridge and 40lbs of propane …besides, what 27 ft unit doesn’t have a fridge that runs shore power and/or propane? That’s just ridiculous.

I should have specified the whole model number. Our first used fiver had the normal RV fridge (propane/electric). I can see why Norcold got the nickname “Nevercold”.

This 12v seems to work just as good as a residential fridge so far.

Other differences I am adjusting to is a 6 gallon propane only water heater. All my water heater have been electic and propane before, with the exception of my Newmar. But in reality it is working great with a very short recovery time.

[5picker]

Originally Posted by FL-Joe

Should have made myself clearer. This new unit has a 12v fridge, not a residential fridge, nor a RV fridge. The OEM solar panel and monitor is dedicated to the fridge only, according to the dealership.

I just wasn’t clear on why the panel showed a couple volt drop at night. Maybe it is displaying something different.

Just hoping someone with same setup in a Salem 32’ would know.

The dealership would be wrong.

As mentioned, the panel and controller work in CONJUNCTION with the CONverter to keep the battery charged when on shore power.

If when on shore power, you actually seen voltages of 11v at night when the solar panel wasn't outputting, then you have something wrong with the CONverter.

[Aussieguy]

to check if converter and battery is working ...... without measuring tools (multi meter)

TEST at night when NO solar is being produced or disconnect the panels


Unplug shore power check inside if any 12v lights or other stuff works


if NO.....
a) turn battery disconnect switch the other position
b) if still no power check the small breakers on the ends of the cables near the batteries


if YES... 12v power coming from battery
disconnect the main negative battery cable that goes to the frame
then connect the 110v shore power
do any lights or other 12v items work?
IF yes then the converter is working


AGAIN......
Only do this while there is NO solar production,
at night or disconnect the panels
----------------------------------------------------------------

If you have a multi meter it is better...
you can measure voltage at the battery and at the fuse panel

if the voltages are around 13.6 when converter is ON then everything is setup / working correctly


If the voltage differs a lot ... check the wiring connections are clean and tight where the converter connects to the fuse panel and at all the connections near the batteries

[FL-Joe]

Originally Posted by Aussieguy

to check if converter and battery is working ...... without measuring tools (multi meter)

TEST at night when NO solar is being produced or disconnect the panels


Unplug shore power check inside if any 12v lights or other stuff works


if NO.....
a) turn battery disconnect switch the other position
b) if still no power check the small breakers on the ends of the cables near the batteries


if YES... 12v power coming from battery
disconnect the main negative battery cable that goes to the frame
then connect the 110v shore power
do any lights or other 12v items work?
IF yes then the converter is working


AGAIN......
Only do this while there is NO solar production,
at night or disconnect the panels
----------------------------------------------------------------

If you have a multi meter it is better...
you can measure voltage at the battery and at the fuse panel

if the voltages are around 13.6 when converter is ON then everything is setup / working correctly


If the voltage differs a lot ... check the wiring connections are clean and tight where the converter connects to the fuse panel and at all the connections near the batteries

Thanks! I will get into it based on your advise. The battery/solar panel quickly recovers to 13.6 after the sun comes. up and stays constant until after dark

[Aussieguy]

are you plugged into shorepower 110v at night?


No.... voltage drop at night is normal


Yes it is plugged into 110v ....
you have to find out why converter is not keeping up


If you come up Tampa way I can meet you and take a look

[PhilFromMaine]

Originally Posted by FL-Joe

Thanks! I will get into it based on your advise. The battery/solar panel quickly recovers to 13.6 after the sun comes. up and stays constant until after dark

The problem is the usage of battery/solar panel terminology. The battery is a storage device and the solar panel is a producer of power. A solar panel won't quickly bring back a battery. It takes a lot of time depending on how much wattage the panels are producing. Therefore, I would guess that your 13.6V isn't correct. I would think based on the fact that your reading is 13.6 at morning hours until sunset that your reading is not a true battery reading and is more of an indicator of receiving solar input.

For testing take truly independent readings of your battery power with no charging sources.

[FL-Joe]

Originally Posted by Aussieguy

are you plugged into shorepower 110v at night?


No.... voltage drop at night is normal


Yes it is plugged into 110v ....
you have to find out why converter is not keeping up


If you come up Tampa way I can meet you and take a look

Thanks for the offer! Probably won’t be up your way until we head to AL later this spring.

[Homer Vista]

Our 3011DS has 100w solar and 12v fridge. It powers up as soon as 12v switch is thrown and will run all day. Haven't tested overnight yet, but I can tomorrow. I'm still trying to find the model number so I can find out how much juice it draws. In process of change to 400AH lithium and 400-600w solar.

[Cruzrtwdgt]

Originally Posted by Beachbourbon

The Salem 270 shows a normal RV fridge and 40lbs of propane …besides, what 27 ft unit doesn’t have a fridge that runs shore power and/or propane? That’s just ridiculous.

Do a little research. Quite a few trailers (my previous 29' Graywolf and my current 34' XLR included ) now use 12v compressor fridges.