RV Fridge is Draining Trailers Battery

Question:

Hi Conner; Thanks again for your response to my questions. I have been perusing your site and understand that I need the BCDC to supply enough current to the run the trailer fridge while travelling. The fridge draws 1400 watts. My questions are: 1) does the BCDC get installed in the tow vehicle or with the battery in the trailer? 2) can I still use the 7 prong plug from vehicle to trailer? 3) does the hot wire need to be changed to a higher grade? If so what size do you recommend? Sorry for all the questions but just trying to get my head around this. Best Regards,

asked by: Gareth

Helpful Expert Reply:

The 12 volt pin on the vehicle's 7-way is mainly used to maintain a charge on a 12 volt battery or charge a small breakaway battery. It will not be sufficient enough to charge a standard 12 volt battery that is used to power appliances on your trailer. In order to keep the battery charged on your trailer you are absolutely going to need a battery charger and for this I recommend the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D. This charger will use power from the vehicle's alternator to charge the battery on the trailer.

I have attached a review video on the above battery charger for you as well.

expert reply by: Conner L

click to enlarge

Gareth

6/19/2018

Conner L.

6/19/2018

Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D will need to be installed on the trailer next to the service battery. You will then need to run wires from the trailer to the vehicle's alternator and battery with quick-disconnects in between the trailer and tow vehicle. The 12 volt power wire on the 7-way should be used to charge the battery on your breakaway system like part # 20099. It will not be connected to the trailer's auxiliary battery as the above battery charger also has a maintenance charge feature therefore will not be needed. In regards to wire size, you will need to refer to the attached chart which takes into account distance and cable type.