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Peakflowa 2021 4c

Scale Prevention System

  • Scale inhibitor
  • Chemical-free and environment-friendly
  • Increases flow rates
  • For up to 10 gpm
  • Residential and commercial
Navien PeakFlow® A scale prevention system
PeakFlow® A certifications
  • Scale inhibitor
  • Chemical-free and environment-friendly
  • Increases flow rates
  • For up to 10 gpm
  • Residential and commercial
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Navien PeakFlow®A... the complete package

Peakflow a pdp

Easy to install with 1" inlet/outlet connections and clips

Peakflow a 25 cover tank

High strength fiberglass tank with a flexible, zippered, neoprene cover


Heavy-duty mounting bracket

Peakflow a 08

Easy to replace PeakFlow media – lasts up to 3 years


Up-flow system design with easy access to distribution tube and upper and lower baskets


Upper basket design prevents media migration, rotates off and on for easy cleaning


Named a 2022 Sustainable Product of the Year by Green Builder Media.

PeakFlow® series video

This highly recommended environmentally friendly system treats hard water issues to address the water quality going into your Navien units, other water-related products and your water supply lines. A “must buy” in areas of hard water. Scale build-up from hard water is the biggest single reason for unit failures.

PeakFlow A prevents scale by converting dissolved hardness minerals into powerless particles that will not attach themselves onto any of the components in the system. PeakFlow A, when sized correctly for the installation, will help to ensure the longevity of your system, and help eliminate hard water quality problems.

Maximum pressure
90 psi/6.2 bar
Maximum temperature
Minimum temperature
Inlet/outlet connections
Service flow rate
up to 10 gpm (23 lpm)
Continuous flow rate
Up to 6 gpm (15 lpm)
Media does not have a grain removal capacity. However, other contaminants present in the water will gradually degrade the effectiveness of this cartridge (see Operation and Maintenance below).
Unit weight
15 lbs/6.8 kg
Unit size (W x H)
5-1/2" x 22-1/2"
Media replacement period
5 years
6.5 to 8.5
Hardness (maximum)
75 grains (1282 ppm CaCO3)
Water Pressure
15 psi to 90 psi (1.03 bar to 6.2 bar)​
40°F to 100°F (5°C to 38°C)
<2 ppm
Iron (maximum)
0.3 mg/l
Manganese (maximum)
0.03 mg/l
Oil & H2S
Must be removed before PeakFlow™A
Must be removed before PeakFlow™A
Silica (maximum)
20 ppm* - PeakFlow media does not reduce silica scaling. While silica tends to have a less significant effect on scale formation than other minerals, it can act as a binder that makes water spots and scale residue outside the plumbing system difficult to remove.
Peakflow a 1 Peakflow a 2
  A B C D E
  in. mm in. mm in. mm in. mm in. mm
PeakFlow A 22.5 572 5.5 140 4 102 3.5 90 12 300

PeakFlow® FAQs

The part number for PeakFlow® A is GPWC3101AC001.

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