Pro-Fill RV Edition - Frequently Asked Questions

A maximum of 6 batteries can be plumbed together with the Pro-Fill RV Edition system, although many users prefer (for ease of filling) to limit the number of batteries plumbed together at 4.


  • Water After Charge - Electrolyte levels drop during discharge and rise during charge. In addition, charging generates heat, fluid expansion and explosive gases.  Watering a battery before charge (or with a low charge level) can lead to boil over resulting in potential damage of the watering system, battery and vehicle. 
  • Water must always be added after fully charging the battery.  If your battery charger has an equalize function it is best to add water after equalizing the battery.  Prior to charging, there must be sufficient water to cover the plates. If the battery has been discharged (partially or fully), the water level should still be above the plates.

Watering intervals are dependent on the local climate, charging methods, application, and age of batteries.  For most RV applications filling once per month is adequate.  High use RV applications may require filling every two weeks. 

No, Leaving a water supply connect to the your SPW system will cause the batteries to be over filled as well as permanent damage to the water supply.  Always disconnect after filling is completed.

Flow-Rite reccomends that batteries are watered on a dedicated schedule to ensure that all batteries get watered.  

1.25 inches after it is installed, although you will need 2.5 inches of clearance for installation.

A typical installation will take an inexperienced person on average 1 minute per battery.


No.  Your Pro-Fill system is designed to be left on your batteries while your vehicle is in winter storage; however, the system will not be operational while it is frozen.
If you have vehicles that are taken out of service or put into storage for a period of 6 weeks or longer, your single point watering system will require seasonal maintenance.  No special steps need to be taken for winterization of the SPW system that is mounted on the batteries; however, the following steps need to be followed when bringing your vehicle back into service:
After the batteries have been fully charged / equalized, connect the system to its water supply for 3-5 seconds then disconnect regardless of whether or not the batteries are completely full.
Return the vehicle to its regular service.
Place the vehicle back into its regular watering schedule (waiting at least 1 week until next watering).

6-Volt or 12-volt “Golf Car” style batteries