Solenoid Valves

Float Valves - Pilot Operated

BFF Pilot float valve or level control valve utilises an external control pilot valve or floating ball valve as the external controller to control the main water tank inlet valve, offering a fully automated mechanical tank refilling system and water level control. 

As the tank water level drops due to water demand the pilot floating valve will also drop and open releasing the back pressure and allowing the main tank refilling valve to open and refill the water tank. The picture on the left hand side shows the pilot floating ball valve in the low level position and the main valve open with mains water supply flow.

As the water tank level rises during the water refilling process the pilot float ball valve will also rise and at the same pre-set level then close generating the required back pressure to close the main water inlet or tank refilling valve. The picture on the right hand side shows the floating pilot valve at the full high or closed level with water back pressure holding the main water tank refilling valve closed. 


The BFF series Pilot float valves offer a compact, cylindrical, robust, high flow, durable piston design, flexible easy, fully automated, maintenance free solution to tank or swimming pool refilling systems without the need for hazardous electrical or complicated mechanical devices. The pilot floating valve can be installed some distance away from the main valve without causing delays in valve performance, as the controlling media is liquid and any loading or controlling pressure are transferred instantly as liquids have very limited compressibility. The BFF float valves are suitable for most cold water storage tanks and offer delayed action water hammer free ON/OFF or OPEN and CLOSED action and can if required be recycled or reused as pressure relief valves, pressure sustaining valves, pressure reducing valves or electrically operated solenoid valves by the exchange for a different external controller circuit, making the BF series control valve a water industry leader in terms of performance, reliability and multi functionality .


Pilot float valve shown on the left with pilot floating ball valve controller.

Valve Materials: Ductile Iron epoxy coated, Bronze, 304 or 316 Stainless Steel

Pressure Range: 0.3 to 16 Bar

Port Sizes: Flange DN50, DN65, DN80, DN100, DN125, DN150, DN200, DN250, DN300, DN350, DN400, DN450, DN500, DN600, DN700, DN800, DN900, DN1000 though to DN1400

Temperature Range: -15°C to +80°C

Working water pressure must be greater than 0.3 Bar


Buy pilot float actuated valves online.


BFF Pilot Float Control Valve location.

1. Outside the tank at floor level

2. Outside the tank above the tank water level

3. Inside the tank above tank water level (check tank wall stress due to extra weight of control valve)

4. Vertically in the rising main. 


Water Strainers / Filters.

It is recommended that a particle or debris strainer is installed upstream of the pilot float main control valve to prevent debris ingress and water control valve failure.


Tank Water Stilling Wells and Baffles.

Generally a stilling well around the BFF Pilot control valve is not typically required unless the float controller has to be mounted close to the water discharge into the water tank, in which case calming measures or a water shield will need to be installed above or around the pilot float to ensure correct float levels during water tank refilling.


Air Gap and Discharge Position.

If an air gap is required for back flow protection, the discharge of the water from the pilot float valve must be above the maximum tank water level. If no air gap is required then the water discharge from the water pilot control valve can be towards the bottom of the tank under the water level, thus reducing water splash and water refilling noise.


Servicing Water Pilot Control Valves.

A servicing valve or manual On/OFF control valve should be installed upstream of the pilot control valve so that it can be isolated during maintenance or in case of emergency. An additional smaller manual isolating valve or water solenoid valve should also be mounted between the main water control valve and pilot float valve for the same reason. 


Optional Extras

A range of accessories are available as original or as retrofit equipment. These include upstream pressure sustaining regulators offering a self regulating pre-set minimum upstream pressure, multiple discharges can be fitted to one water tank and partitioned tanks.



The BFF patient cylindrical piston pilot water float control valve design offers the mos rugged internal and external structure and typically packaged in strong twin wall export carton or plywood export carton depending on size, weight and customer requirements at no extra cost. However the pilot floating ball valve itself is not included and will need to be purchased elsewhere.


Closing Speed Opening Speed BFF Pilot Control Valve.

The opening and closing speed of the pilot control water valve is factory set between 3 to 5 seconds depending on size and water pressure which avoids excessive pressures (water hammer) developing in the supply pipe as the water control valve closes. The BFF valve will never BANG and cause water hammer and no adjustment is required.


High Flow Water Tank Refilling.

The BFF pilot water control valve is cylindrical in design with a very robust internal piston (no weak diaphragm) that is fitted with a high pressure hydraulic cylinder type self cleaning U ring. The design of which not only dramatically improves working life of the water valve but also offers exceptional flow as compared to other water tank pilot float valves of similar size, therefore improving water flow and reducing pipework size and costs.











































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