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Tankless Flush Kit

Tankless flush kits and maintenance supplies keep heat exchangers clean, efficient, and under warranty. Build your setup with a recirculating pump, service hoses, isolation/flush valves, and a safe descaling solution—then add filters and neutralizers for long-term protection.

Shop by need

  • Complete flush kits: pump + hoses (and bucket on select kits) for annual descaling
  • Isolation/flush valve sets: hot/cold service valves with drain ports for easy maintenance
  • Descalers: citric/biodegradable cleaners and white-vinegar alternatives; manufacturer-specific solutions
  • Filters & scale prevention: sediment filters, scale inhibitors, and replacement cartridges
  • Condensate neutralizers: inline kits and media refills for condensing units
  • Accessories & parts: service port gaskets/caps, hose washers, test strips, and replacement pumps/hoses

Quick choosing guide

  1. Confirm your valves: if you don’t already have isolation/flush valves on the heater, add a valve set with service ports first.
  2. Pick a kit: choose a complete kit for first-time maintenance or pump/hoses only if you already have valves and cleaner.
  3. Choose the cleaner: use a manufacturer-approved or citric-based descaler. Avoid harsh acids; follow the label for dilution.
  4. Protect against future scale: add a sediment filter and (in hard water) a scale-inhibitor ahead of the heater.
  5. Condensing units: install or refresh a condensate neutralizer to protect drains and meet code.

Flush basics (always follow your manual)

  1. Turn power/gas off and close hot/cold isolation valves. Relieve pressure.
  2. Connect hoses to the service ports; place pump intake in descaler solution and return hose into the bucket.
  3. Open service ports and recirculate 45–60 minutes (or per cleaner instructions).
  4. Drain, then flush with clean water 5–10 minutes. Close ports, remove hoses, and restore power/gas.
  5. Check for leaks and run a hot-water tap to purge air.

How often? Typical interval is every 6–12 months (more often with hard water or heavy use). 

  • Rinnai - MIVK-T-LW - Matsui Plumbing Isolation Valve Kit

    Rinnai
    Original price $ 93.00 - Original price $ 93.00
    Original price
    $ 93.00
    $ 93.00 - $ 93.00
    Current price $ 93.00

    Rinnai Isolation Valve Kit The Rinnai MVIK-T-LW tankless water heater valve kit facilitates a streamlined, two-step installation process for your ...

    View full details
    Original price $ 93.00 - Original price $ 93.00
    Original price
    $ 93.00
    $ 93.00 - $ 93.00
    Current price $ 93.00

Pro tips: Label service valves “hot/cold,” replace hose washers each season, and keep a spare bottle of descaler on the shelf. Add inlet filtration to reduce future scale, and refresh neutralizer media yearly on condensing units. Not sure which kit fits? Tell us your heater brand/model, valve size (3/4" or 1"), and water hardness—we’ll build a dialed-in maintenance package.

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