O P E R A T I O N A N D M A I N T E N A N C E M A N U A L
PAGE # 17
PF-50 Series Filter (ver. 4/5/05)
OPERATION IN COLD WEATHER
When the PF-50 series filter is exposed to below-freezing temperatures, it will require protection to prevent
freezing. An indoor installation in a heated room is the best way to preventing freezing of any liquid in the
filter unit. If an indoor installation is not practical, supplemental heat must be supplied. Heat tape and
insulation around the liquid filled filter components must be used to prevent freezing. The filter unit
should be drained when not in use for long periods of time. Refer to shutdown procedures below.
SHUTDOWN
The following services should be performed when the unit is to be shutdown for a prolonged time period.
1. Run the filter unit through a complete backwash cycle.
2. Shut off and lock out all electrical power.
3. Close the service valves in the filter inlet, outlet and backwash lines.
4. Relieve all pressure from the filter vessel and piping. Open the manual relief valve located on top of the
vessel, and leave the valve open.
5. Drain all external piping to and from the filter.
6. Remove the drain plug on the filter vessel. Allow the liquid to drain. After all liquid has drained replace
the drain plug. If supplied, open the drain plug on the pre-strainer housing. Allow all the liquid to drain and
then replace the drain plug.
7.If supplied, remove the bolts from the pump pre-strainer cover. Remove the cover, and clean debris from
the pump pre-strainer basket. Inspect the gasket and lubricate (replace gasket if necessary.) Replace the
basket and cover and tighten bolts.
8. Remove the top handhole/manhole cover by removing the hex nut on the crab clamp by pushing the
handhole/manhole into the vessel (do not drop handhole/manhole). Remove and inspect the gasket.
(replace if necessary)
9. Inspect the media for foreign material. Over a period of time, a build up of debris may become imbedded
in the media which cannot be backwashed out. Contaminated media should be discarded. If the media pack
is contaminated, replace the media. If the media is removed thouroghly inspect the internal assembly before
loading new media. Refer to Loading Media and Table IV (page 7) . Re-install the handhole/manhole cover.
10. Close the manual air relief valve located on the top of the vessel.
