More charge power ?

[tortue71]

Is there a way to get the truck to charge the rv battery more while travelling ?

While using the furnace on the road , I am not able to keep the battery charged up .

thanks

[Grumpy]

Originally Posted by tortue71

Is there a way to get the truck to charge the rv battery more while travelling ?

While using the furnace on the road , I am not able to keep the battery charged up .

thanks

Are you sure you have 12v going from the truck to the trailer?

[tortue71]

Originally Posted by Grumpy

Are you sure you have 12v going from the truck to the trailer?

Yes , i'm just using more power than the truck can charge because of the small wire.

[shadester]

The furnance is a high draw item. Only way I could see charging your battery faster is with a high guage wire with a isolation solnieod or isolation diode from the truck. Also, I would take into consideration the output of your truck alternator.

[Grumpy]

Originally Posted by shadester

The furnance is a high draw item.

Many people claim they get two nights running the furnace and lights boondocking. So if OP has a fully charged battery the line from the truck should maintain the battery enough for one days travel.

[oldmanAZ]

Originally Posted by tortue71

Is there a way to get the truck to charge the rv battery more while travelling ?

While using the furnace on the road , I am not able to keep the battery charged up .
thanks

Charging more would require running a heavier gauge wire back to the trailer and possibly to the battery. The standard wire size is too small for what you have in mind and has a significant voltage drop and limited the current capacity to the trailer battery. Do you have 'upfitter switches' in your TV or is it the standard trailer wiring?

Have you measured your trailer battery voltage in the morning?

How many hours do you usually drive the day after you ran the furnace?

How may hours do you run the furnace? (Just overnight/in the afternoon/overnight/etc.)

I feel your pain. I'm in a similar boat.

[tortue71]

Originally Posted by Grumpy

Many people claim they get two nights running the furnace and lights boondocking. So if OP has a fully charged battery the line from the truck should maintain the battery enough for one days travel.

it's because when I left home , the temperature was -13 fahrenheit, so the furnace never stopped until I got south enough , but it took 12 hours. When I stopped for sleepig a little bit , I had no juice left in the battery , I had to let the truck idle to keep heating while I slept.

[tortue71]

Originally Posted by shadester

The furnance is a high draw item. Only way I could see charging your battery faster is with a high guage wire with a isolation solnieod or isolation diode from the truck. Also, I would take into consideration the output of your truck alternator.

Alternator is not a problem , I have two

[tortue71]

Originally Posted by oldmanAZ

Charging more would require running a heavier gauge wire back to the trailer and possibly to the battery. The standard wire size is too small for what you have in mind and has a significant voltage drop and limited the current capacity to the trailer battery. Do you have 'upfitter switches' in your TV or is it the standard trailer wiring?

Have you measured your trailer battery voltage in the morning?

How many hours do you usually drive the day after you ran the furnace?

How may hours do you run the furnace? (Just overnight/in the afternoon/overnight/etc.)

I feel your pain. I'm in a similar boat.

Yes , that's what i'm looking for actually , I'll run a wire from the front and wire the trailer and put another connection there to charge when I need it. I do not have a generator so I would like to use the truck for that. I know i'll only have 12 volts that way.

Maybe I could use a big inverter in the truck while it's running , that way I could use 120V in the trailer and It would charge my battery at the same time.

I have a diesel with dual alternators so I don't think that while the truck is running I would have any problems.

[Grumpy]

Originally Posted by tortue71

it's because when I left home , the temperature was -13 fahrenheit, so the furnace never stopped until I got south enough , but it took 12 hours. When I stopped for sleepig a little bit , I had no juice left in the battery , I had to let the truck idle to keep heating while I slept.

If you could run the furnace with the truck running after you stopped then you have something else wrong. The truck would have supplied enough power for the furnace while driving and there would not have been any excessive draw on the battery.

[shadester]

Originally Posted by tortue71

Alternator is not a problem , I have two

That's another option, if you have the room.

[Mustang65]

Install 2 100 watt SOLAR panels on the TT's roof. While traveling we run our fridge on 110VAC (1500watt inverter) with the SOLAR panels. My 250Watt panel produces 20 amps out of the MPPT SOLAR Charge Controller to the batteries, when needed. Most of the trip the batteries are taking about 10 - 15 amps. We always arrive with a full charge on the batteries and a cold fridge. The heating system would be a walk in the park for SOLAR.

As far as power from you TV, what year/make is it. I have a 2012 F150 and the alternator is rated over 200 amps, not sure if it was 240 amps. The problem is the supply wire to the rear towing receptacle, like most others. The 2012 or 2013 Ford trucks were the last year(s) that you could actually run an new 8AWG wire from the battery (fused) to the trailer receptacle and not cause any charging issues as the newer trucks have their 12 volt supply to the receptacle running through a microprocessor controlled current monitoring circuit which works with the charging systems microcontroller. Not really a good idea to be wiring around that.

That will not be you only issue... the wire on the TT from the TV plug to the connector (usually in a 4x4 electrical box on the frame near the tongue) is the same gauge wire as the TV, you will need to replace that wire also.

Don

[Bassdogs]

Seems like what you experienced is a unique rare type situation. How many times are you going to head out when temps are below zero and drive for 12+ hours with your furnace running? You are trying to solve a problem that only exists in a very rare situation so does it make a lot of sense to spend $$$$ to fix it??

Suggestions: take a 2nd fully charged battery to use for the overnite when you make that first stop. Even better, heat up the interior of the RV using house power at home so you have a heated RV when you leave. It won't hold the heat but the interior will be well above freezing when you make your overnite stop without having to run your furnace while you are traveling. You arrive for your overnite with a fully charged battery with a camper that may still be in the 30's inside when you stop. Fire up the furnace and head across the parking lot for dinner and your interior s/b up to 60 or more by the time you get back. It won't be starting from a -13 temp and assuming the outside temp should rise as you head south it will heat up to a comfortable temp pretty fast.

I'm guessing that in addition to running your battery down, you probably blew thru most of a 20lb propane bottle. A couple years ago we left home at 10 below and drove about 6 hours before stopping in mid Ala. Temp when we stopped was only up to 19 degrees. I used the above plan and when we got back from the steakhouse it was 60 inside the TT. We have twin 6V cart batteries so we made it thru the night with the fan still running [much slower] by sun up. Furnace off and hit the road and battery was fully charged when we made our 2nd overnite and temps were still only in the low 40's so we were good for another warm nite.

Is there a reason you think you have to run your furnace all day while you are on the road?

[DanNJanice]

Originally Posted by tortue71

Yes , that's what i'm looking for actually , I'll run a wire from the front and wire the trailer and put another connection there to charge when I need it. I do not have a generator so I would like to use the truck for that. I know i'll only have 12 volts that way.

Maybe I could use a big inverter in the truck while it's running , that way I could use 120V in the trailer and It would charge my battery at the same time.

I have a diesel with dual alternators so I don't think that while the truck is running I would have any problems.

Hmmm, I don't think the inverter is a real great idea. There are a lot of losses from the up/down voltage conversions. Just a few amps of draw at 120VAC would translate to 20-30 amps being drawn from you 12V source.
It is unclear what kind/size of trailer you have. The furnace(really the fan) in my 27RLS draws about 5-6 amps. My truck can supply about 10amps at most through the factory wiring and trailer plug. However, that is still enough that I could supply the furnace indefinitely if the truck is running.
My guess is you have something else going on. Either more draw that you think or your truck is not actually supplying anything to the charging wires to your trailer.
If you do not already have one, I highly recommend you get a clamp-on DC amp meter. This will allow you to check the charge/discharge current simply by clamping on to the battery cables.
I have a Uni-T UT210E meter which is OK for RV work and can be picked up on Amazon for about $35.