Rinnai-Compatible Water Filter Maintenance
SpringWell CF4 catalytic carbon tank (paired with Rinnai): no maintenance for 10 years (1,000,000-gallon media life). Pelican PC600 KDF + carbon tank: no maintenance for 5 years (600,000-gallon media life). Moen MFILTPRO (cartridge-based): replace main cartridge every 6 months ($40--$65 at Home Depot). Rinnai descaling kit (RCS-K, $25--$35): annual use regardless of water treatment, available through Rinnai authorized dealers and Amazon. Water softener salt (if applicable): 40--50 lbs per month at 10 GPG inlet hardness. The combined annual maintenance cost for a Rinnai household with full water treatment (spring CF4 media + softener salt + annual Rinnai descaling): approximately $150--$300 per year -- a fraction of the heat exchanger replacement cost it prevents.