F76S-11/4AA Honeywell filter with backwashing

Backwashing filter for effective system protection

The F76S-11/4AA model was designed as an efficient fine mesh water filter that protects fittings, valves, appliances, and sections of the installation against mechanical deposits. It captures foreign bodies present in the water, including rust particles, hemp fibers, and sand, reducing the risk of failures and premature wear of system components.

A major advantage of this solution is the ability to perform backwashing without shutting off the supply of filtered water. This makes the filter suitable for both domestic water installations and industrial environments where uninterrupted operation is important.

All components of the device meet the requirements of current DIN/DVGW standards. The design has also been manufactured in accordance with KTW recommendations for drinking water.

Key advantages of the Honeywell F76S-11/4AA filter

• Filtered water is supplied even during backwashing.
• The patented backwashing system is fast and allows the filter to be cleaned using a small amount of water.
• A special setting ring indicates when the next backwash should be carried out.
• The filter can work with an automatic backwashing unit.
• The large filtration area supports efficient device operation.
• The transparent filter bowl made of impact-resistant synthetic material makes it easy to monitor the degree of contamination of the cartridge.
• The replaceable filter insert and bowl make servicing and continued operation easier.
• Very simple operation supports everyday use.
• Manufactured in accordance with KTW recommendations for drinking water.

Operating principle

The Honeywell F76S-11/4AA filter operates based on a well-designed cartridge structure and an effective backwashing mechanism, enabling thorough cleaning of the filter screen without disassembling the device.

• The filter insert consists of an upper and a lower part.
• With the knob in the “filtration” position, the upper filter insert is closed so that water passes only through the lower main insert from the outside to the inside.
• When the ball valve is opened to perform backwashing, the main filter insert is moved downward until the water supply from the outside is stopped. At the same time, the water flow to the upper part of the filter is opened.
• For connection sizes from 1/2" to 11/4", backwashing uses the so-called double spiral method, allowing simultaneous cleaning of the filter screen in the upper and lower parts of the filter insert.
• The water used for cleaning passes through the screen, rotor, and main filter insert from the inside to the outside. This means that the insert is thoroughly cleaned over its entire surface at full inlet pressure.
• The filter automatically returns to the operating position after the ball valve is closed.
• The internal rotor flushes impurities adhering to the screen out through the discharge openings.

Design and contents

The filter design was developed with durability, easy handling, and convenient access to working components in mind.

• Housing with pressure gauge
• Threaded connections
• Fine mesh filter insert
• Transparent filter bowl
• Ball valve with drain cover
• Box wrench for the filter bowl

Materials

The selection of materials affects corrosion resistance, service life, and safe operation in the water installation.

• Housing made of dezincification-resistant brass
• Threaded connections made of brass
• Filter insert made of stainless steel
• Filter bowl made of red brass or impact-resistant transparent synthetic material
• Seals made of nitrile rubber (NBR)

Installation and installation guidelines

Correct installation of the filter directly affects its effectiveness, ease of use, and ease of later maintenance.

• Horizontal installation with the filter bowl facing downward – this position ensures optimal efficiency.
• Installation of shut-off valves on both sides of the water meter.
• Ensure access to the device so that the pressure gauge is clearly visible – with the transparent filter bowl, the level of contamination of the filter screen can be easily determined, which facilitates maintenance and inspection.
• Install directly downstream of the water meter in accordance with DIN 1988, Part 2.

Operation and everyday use

The F76S-11/4AA model was designed for convenient operation. The transparent cover makes it easier to assess the contamination level of the filter screen on an ongoing basis, while the pressure gauge supports monitoring of operating parameters. A special setting ring helps determine the time for the next backwash, organizing routine service activities.

Backwashing allows the insert to be refreshed without interrupting the supply of filtered water to the installation. This is an important feature in more advanced systems where the water filter is the first stage of equipment protection. Such an element complements broader solutions used in domestic water preparation systems, including where an osmotic filter, reverse osmosis filter, reverse osmosis unit, or a complete reverse osmosis system is used later.

Additional important information

• Threaded connections
• KVS value: 22

Technical specifications

FAQ