4-Stage High Capacity RO Replacement Filter kit

4-Stage High Capacity PureWaterMachine Reverse Osmosis System

for Vertex 3C-4.0 SKU: FK-102

Vertex 3C - 4.0 | 4 - Stage High Capacity RO Purifier Annual Filter Kit - FK - 102 - Pure n Natural Systems

4-Stage High Capacity RO Replacement Filter kit

4-Stage High Capacity PureWaterMachine Reverse Osmosis System

for Vertex 3C-4.0 SKU: FK-102

$85.95

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About this product

Replacement Filter kit for 3C-4.0 Vertex High Capacity PureWaterMachine Reverse Osmosis System 

The FK-102 Annual Filter Kit is designed to maintain performance and water quality in High-Capacity 3C-4.0 reverse osmosis systems. This kit replaces the essential pre- and post-filtration stages that protect the RO membrane and polish the final drinking water. By removing sediment, reducing chlorine, and improving taste and odor, the FK-102 kit supports consistent system operation and reliable year-round filtration when replaced annually.

RO Membrane sold separately.

Best for
  • High-capacity Vertex 3C-4.0 reverse osmosis (RO) systems
  • Annual replacement of pre-filters to maintain RO performance
  • Protecting the RO membrane from sediment and chlorine exposure
  • Commercial, office, and high-use drinking water applications
  • Users following manufacturer-recommended yearly maintenance

Specifications

What's in the box
  • 1 - Stage 1 - 5 micron Sediment Filter
  • 1 - Stage 2 - Activated Carbon Block Filter
  • 1 - Stage 4 - High Capacity Coconut-Shell Activated Carbon Post Filter
  • 1 - Filter Wrench
  • 2 - "O" Rings
  • Instruction Manual

RO Membrane sold separately.

Installation tips
  • Shut Off Water Supply: Turn off the feed water to the RO system before servicing.
  • Relieve System Pressure: Open the RO faucet to release pressure from the system.
  • Use the Included Filter Wrench: Loosen the filter housings using the supplied wrench.
  • Replace Stage 1 – Sediment Filter: Remove the used 5-micron sediment filter and install the new one.
  • Replace Stage 2 – Carbon Block Filter: Remove the existing activated carbon block and install the replacement filter.
  • Replace Stage 4 – Carbon Post Filter: Remove the used high-capacity coconut-shell carbon post filter and install the new one.
  • Inspect and Replace O-Rings: Use the included O-rings if existing seals are worn or damaged.
  • Reassemble Housings: Tighten housings securely by hand (do not overtighten).
  • Restore Water Supply: Turn water back on slowly and check for leaks.
  • Flush the System: Flush the system according to the instruction manual before using the water.

Frequently asked questions

Which systems is the FK-102 filter kit compatible with?
This kit is designed for High-Capacity 3C-4.0 reverse osmosis systems that use the FK-102 filter configuration.

Does this kit include a reverse osmosis membrane?
No. The FK-102 kit does not include an RO membrane. It includes the sediment, carbon block, and carbon post filters only. The RO membrane is replaced separately on a longer service interval.

Why does this kit include a Stage 4 carbon post filter?
The Stage 4 high-capacity coconut-shell activated carbon post filter provides final polishing of the water, improving taste and odor after RO filtration.

How often should the filters in this kit be replaced?
The filters in the FK-102 kit are intended to be replaced once per year under normal operating conditions, or sooner if water quality or usage is unusually high.
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