The Polaris Backup Valve is located on the Polaris Leader hose and is responsible for pulling the Polaris Cleaner away from pool obstacles and increases its random pattern.
The Replacement Polaris Backup Valve Kit is suitable for all Polaris Pressure Cleaners (Polaris 3900s, Polaris 280, Polaris 380 and Polaris 180).
To check whether is Polaris Back up Valve is functioning properly simply lift it out of the water and approximately every 3 miniutes the valve should go into back-up mode where water is thrusted out of the valve.
If the valve does require replacement, unscrew the plastic nuts securing the valve on both sides to the hose and remove the valve. The hose nuts are then placed back onto the Polaris Back Up Valve and then are screwed onto the hose.
It is also possible to just replace the internal mechanism of the Polaris Back Up Valve. This can be difficult as the collar for the Polaris Back Up Valve needs to be removed.