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Understanding Water King’s Media Filter Line

(Discussion includes model and part number explanations.)

A filter consists of a vessel, containing media, with valves to facilitate backwashing. Media filters can be backwashed or cleaned and then returned to service. All of Water King’s filters are vertical tank, down flow filters.

Filter Vessels - The three different vessel configurations are:

1.       Fiberglass vessels with top mount valves

2.       Fiberglass vessels with side mount valves where the water is piped to the top and bottom of the vessel and the valves are side mounted. This piping is commonly called “face piping”.

3.       Steel tanks with face piping and side mount valves.

Filter Valves - Water King uses three types of fully automated valve systems:

1.       The Flow Master Valve is a plastic top mounted valve with ¾” or 1” pipe. It is installed top mounted on fiberglass tanks.

2.       The Task Master III stainless steel valve can be top mounted on fiberglass tanks or side mounted as a part of face piping on fiberglass or steel vessels. The Flow Master and Task Master III are commonly called five cycle valves since they operate to cause all five cycles of softening or filtration to occur in a single valve.

3.       Valve nests for filters are mounted in the face piping of a system and perform all of the functions of the five cycle valves by opening and closing six valves for a softener or five valves for a filter. Standard valve nest systems use cast iron diaphragm valves controlled by a multi port pilot valve or stager.

Filter Systems - These vessels and valves combine to create six filter configurations or lines. 

1.       The Bayou Series Filters (FBF) have the Flow Master valve in a top mount configuration on a fiberglass vessel.

2.       The RF series filters (FRF) have the Task Master III valve in a top mount configuration on a fiberglass vessel.

3.       The MF series filters (FMF) have the Task Master III valve in a side mount configuration on a steel vessel.

4.       The MF series filters using fiberglass vessels (FMF FG) have the Task Master III valve in a side mount configuration on fiberglass vessels.

5.       The VN series filters (FVN) have a valve nest side mounted on a steel vessel.

6.       The VN series filters using fiberglass vessels (FVN FG) have a valve nest side mounted on a fiberglass vessel.

Water King uses six types of media, neutralizing (-N), filter AG (-T), sand (-S), activated carbon (-C), manganese green sand (-I), and multi media (-MM).

Model Numbers

Model numbers for the FBF, FRF, FMF and FMF-FG lines consist of the letter designation, the size which is a number corresponding to a softener capacity of the same size, and the media. Thus a 16 inch diameter fiberglass sand filter with a top mount Task Master III would be an FRF 120 – S, where the 120 represents a 16 inch diameter softener. Model numbers and corresponding diameters are located HERE.  

For valve nest systems the diameter is simply listed so that an FVN 60 – I is a 60-inch diameter steel tank manganese greensand valve nest filter.

Filters Without Media

Note that filter part numbers follow a similar set of designations for the valve and vessel type and media in the vessel.  Click here to view Filters  (less media)  Part numbers.

For a given filter model, the only variation between the different types of media is the backwash rate. There are three standard backwash rates for each vessel size yielding backwash rates of 8-10 , 10-12, and 15 gpm/ft2. These values are tabularized for each model. A filter vessel and valve without media does not carry a media designation, no dash or extension to the model number, and the fourth digit of the part number is a zero. If you wish to specify a filter (less media) use the part number with the fourth digit as zero and add an extension specifying the backwash flow rate. For example, an FMF 300 filter without media set up for 35 gpm would have a part number of 929030-35 with 929 for the FMF series, 0 for no media, 30 for a model 300 at 30” diameter, and –35 for 35 gpm back wash. A table is given to explain the part numbers. Note the list of number designations for media types.

Continuing, if we wanted our filter to have a 125 psi ASME code vessel we would add and extension – 125S making the part number 929030-35-125S, (S means ASME code with a Stamp.) A list of part number and model number extensions is provided and can be found HERE.

Filters With Media

For a filter with media we use the fourth digit to designate the media. For example a 929530 is an FMF 300 –S or 30” diameter steel tank sand (5) filter with a Task Master III valve. The backwash designation is not required since specifying the media constrains the backwash rate to match the media.  A table is given to explain the part numbers.


Water King, Inc. S 102 Charbonnet Road  S Duson,  LA  70529  S (337) 988-2360 S (337) 981 - 7922 FAX