Stop removing caps one by one and wrestling with a funnel. The Flow-Rite Pro-Fill system replaces every vent cap on your 36V battery bank with automatic shut-off valves, links them with precision tubing, and lets you fill all cells in a single connection -- every time, to the exact right level, without overflow or dry cells.
The Flow-Rite Pro-Fill system is purpose-built for 36V battery banks where batteries are spaced in non-standard configurations -- common in older golf carts, industrial equipment, floor scrubbers, and custom RV house bank builds where cells are not evenly or conventionally spaced.
Each automatic shut-off valve replaces the existing vent cap on your flooded lead-acid battery. Valves are interconnected with flexible tubing routed through the bank. When you attach the water source and squeeze the hand pump, each valve fills its cell and snaps shut automatically when the correct electrolyte level is reached. No guessing. No overfilling. No acid spills.
Each valve closes independently at the correct level -- prevents overfilling and electrolyte dilution.
Tubing and valve layout designed for batteries not in a standard even-spacing configuration.
Self-priming hand pump connects to a standard water jug or fill station -- no tap or pressure source required.
Configured for a 36V bank -- typically six 6V batteries or three 12V batteries wired in series.
Standard Pro-Fill kits ship with tubing lengths optimized for batteries in a uniform, evenly spaced tray. If your batteries are in a staggered layout, offset rows, or an irregular enclosure, the standard tubing will not reach cleanly between cells. The non-standard spacing variant (this kit) provides the tubing and routing flexibility needed to fit those irregular configurations without kinking or excessive slack.
This system is designed for flooded lead-acid (FLA) batteries with removable vent caps -- the type that requires regular distilled water top-off to maintain electrolyte levels. It is not compatible with sealed AGM, gel, or lithium batteries (those types do not use vent caps or require watering).
Flow-Rite Pro-Fill valves are designed to fit standard battery vent cap openings. The most common opening size is 1.125-inch diameter. Verify your battery vent cap opening before ordering. Flow-Rite offers valves in multiple thread/snap-fit configurations -- confirm the valve style in this kit matches your specific battery brand and model.
The included hand pump is a manual squeeze-bulb or lever-action pump (depending on kit revision) that draws water from a standard distilled water jug or portable fill station. You connect the pump outlet to the single fill point on the battery bank manifold, pump until flow stops -- indicating all cells have reached shutoff -- then disconnect. Total fill time for a 36V bank is typically under two minutes once the system is installed.
The hand pump in this kit is ideal for locations without a water source nearby. If your RV storage bay or equipment room has access to a low-pressure water line or a raised gravity tank, Flow-Rite also offers Pro-Fill kits compatible with pressurized fill stations and de-ionized water systems. The shut-off valves in this kit are compatible with those sources as well -- the hand pump is simply the included fill method.