Using golf cart batteries to provide 12-volt DC house power is efficient and cost effective. It’s common practice to replace two 12-volt batteries wired in parallel with 6-volt golf cart counterparts wired in series because they have the same footprint and provide additional capacity for non-hookup service. They are also more durable, can take deeper discharges and withstand many more charging cycles.
The downside is golf cart batteries have a higher profile, so in many cases access to the caps to add water becomes restricted when mounted in tight compartments. Since open-cell batteries need to be topped off regularly, owners relegated to mirrors and turkey basters are sometimes neglectful when it comes to adding water because they dislike the process. The Pro-Fill on-board battery watering system takes the stress out of battery maintenance.
There are various kits are available, depending on battery type and number of batteries, but the company offers a dual 6-volt system designed specifically for this application. Special valves attached to manifolds replace the existing cell caps and fit the golf cart batteries — using standard 2 11/16-inch spacing — right out of the box.
Installation is simple, but heed a few precautions. First, you’re dealing with open cells and electrolyte, which is battery acid. It’s easy to burn skin, clothing and eyes if proper protection is not employed. Second, make sure the water level is topped off and the batteries are fully charged. Neglected batteries that are filled with water just prior to the installation of the Pro-Fill valves are subject to water level expansion while charging, which leads to messy spillage and corrosion.
Once the original caps are removed, the valves are installed using a 1/4-turn to lock in place. If your batteries have other than standard cell spacing, the system can be customized using flexible manifolds that come with the kit. The manifolds are linked using a length of tubing that’s cut from the 5-foot piece attached to the quick connect coupler. Five feet is more than enough tubing so cutting from the free end presents no installation complications. There are three barbs on each manifold for tubing routing. The fill tubing is connected to a barbed fitting on one manifold and the extra fittings are capped. Up to six batteries can be configured with one fill tube.
Pro-Fill’s optional Handy Pump is used to fill the batteries by using the aforementioned tubing attached to the batteries via the quick connector. One end of the Handy Pump tubing is put in a jug of distilled water (positioned below the batteries to avoid siphoning) and the bulb is squeezed until it becomes hard, letting the user know the cells are filled. The automatic shut-off feature in each valve prevents overfilling.
The process is clean, simple and convenient, and leads to healthy battery maintenance. Kits are made in the USA and sell for around $70; the Handy Pump is $21. Pro-Fill RV Battery Watering Systems are available at Camping World stores.