Stop lifting battery caps one at a time and risking acid overfill. The Flow-Rite Pro-Fill system connects all cells across nine 8V deep-cycle batteries into a single-point watering circuit -- fill every cell to the correct level in one shot, with automatic shut-off valves that stop flow the instant each cell reaches its proper level.
The BG-U72V-5A is engineered specifically for battery banks made up of nine 8-volt deep-cycle batteries with 2.3-inch center-to-center cell spacing -- the standard found in many golf cart and RV house bank configurations. This is the "Universal" variant, meaning the tubing is pre-measured and the manifold is configured at the factory for this exact cell count and spacing. No cutting or custom routing is required out of the box.
The system replaces the existing vent caps on every cell with Flow-Rite's automatic shut-off valves. These valves are interconnected by a tubing network that runs from cell to cell and terminates at a single remote fill port. Connect a standard water supply or hand pump to that fill port and water distributes to every cell simultaneously. When a cell reaches its correct electrolyte level, its shut-off valve closes -- preventing overfill and acid damage to battery tops, cables, and surrounding structure.
One fill port services all 9 batteries and all 54 cells in a single operation -- no removing caps, no checking levels individually.
Each valve stops flow independently the moment its cell reaches the correct electrolyte level, eliminating overfill risk.
Pre-measured tubing and manifold sized for nine 8V batteries at 2.3-inch cell spacing -- no custom cutting required.
Valves, tubing, and fittings are built from materials rated for continuous contact with lead-acid battery electrolyte.
The BG-U72V-5A kit ships complete and ready to install. Contents include:
Note: A water supply pump or hand pump is NOT included. Flow-Rite sells compatible hand pumps and battery filler bottles separately.
Deep-cycle lead-acid batteries lose distilled water through normal charge and discharge cycling. Plates that are exposed to air sulfate rapidly and permanently lose capacity. Overfilling dilutes electrolyte concentration and can cause acid overflow during charging, corroding terminals, cables, and battery trays. The Pro-Fill system removes both failure modes -- it will not stop until every cell has water, and it will not overfill any cell.
This kit is designed for flooded (wet cell) lead-acid deep-cycle batteries. It is not compatible with AGM, gel, or sealed maintenance-free batteries, which have no accessible fill ports.
Flow-Rite offers Pro-Fill kits in multiple configurations to match battery count, voltage, and cell spacing. The BG-U72V-5A is specifically for nine 8V batteries at 2.3-inch cell spacing. If your bank uses 6V batteries, 12V batteries, a different cell count, or a different physical spacing, you will need a different part number. Measure cell center-to-center spacing before ordering to confirm fitment.
Installation requires no special tools beyond basic hand tools. The general process is:
Always use distilled water only. Tap water contains minerals that accelerate sulfation and shorten battery life.