Ultima II Winter Shutdown
The Ultima II can run year round in fair weather conditions. If you shut down your filter system for the winter, then you will need to follow these instructions.
Backwash the Ultima II at least a couple times. You will want the filter to be as clean as possible for shutdown. Any waste that is left in the filter will sit and fester while it is shut off.
Turn off the pump, disconnect or drain the pipes that connect the filter to the pump and other filter system components.
Set the valve to the winter setting. This leaves the ports open to prevent water from freezing in the filter.
Unscrew the drain cap on the bottom of the filter. Water should drain at a decent pace, if it trickles out after you removed the drain cap, there may be waste that's still in the filter. Replace the cap and run another backwash cycle to unclog the filter.
The media inside the filter will hinder the flow of water draining out of the filter, so it will take some time.
Secure a cover over the valve assembly, this will prevent dust and other debris from obstructing the valve movement when it's not in use.
When starting the Ultima II back up in the spring, uncover the valve, replace the drain cap, and perform a backwash to clean any residual waste that was left in the filter.