The Trailer Owner's
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M4

Fresh Water System Sanitation

Clean water in. Clean water out. Every six months, no exceptions. Total time: 5–6 hours (about 1 hour active).

⏱ 5–6 hours (1 active)

Your fresh water system is a closed environment that can harbor bacteria, mold, and biofilm if it isn't periodically sanitized. This is the full sanitation procedure — the correct bleach concentration, how long to let it sit, how to flush it completely, and how to verify you're done. Plan for a morning to do it right.

Run this procedure at least every 6 months. Also run it any time you notice an off smell or taste in your water, after purchasing a used trailer, after using a questionable water source, or after the trailer sits unused for 2+ months.

⏱ Most of the time is the bleach soak (4–8 hours unattended). Start in the morning, soak all day, flush in the evening.

When You Need This

Supplies

Step 1 — Prep (10 min)

Step 2 — Mix & Add Bleach Solution (10 min)

The Formula

¼ cup of plain bleach per 15 gallons of fresh tank capacity. Pre-dilute in 1 gallon of water before adding to tank. Never pour undiluted bleach directly in. Examples: 30-gal tank = ½ cup bleach · 45-gal = ¾ cup · 60-gal = 1 cup

Step 3 — Distribute Through System (15 min)

⏱ Soak: 4–8 Hours Minimum. Leave the bleach in the system for at least 4 hours. Overnight (8–12 hours) is better. Do not use any water during the soak. Set a reminder and walk away.

Step 4 — Flush & Rinse (30–45 min)

Clear the Bleach Fully Before Drinking. You may need 2–3 full tank flushes. The water is not ready to drink until it smells and tastes completely neutral.

Step 5 — Finish (10 min)

  • Install fresh water filter cartridgesnew ones only
  • Turn on water heater and let it heat for 20–30 minutes
  • Run hot water at each faucet brieflyconfirm temperature and no bleach smell in hot lines
  • Check under sinks and trailer for any drips

Troubleshooting

Eggy or Sulfur Smell — But Only in Hot Water? Your water heater anode rod is the culprit — not the tank. Replace the rod (see Spring Startup Step 4 for full procedure) and the smell typically clears within 1–2 uses.

  • Persistent odor after 3 flush cycles: replace water filter, re-run sanitation with a longer soak
  • Smell only in hot water: replace anode rodsee Spring Startup checklist Step 4
  • Bad taste after purchase of used trailer: run sanitation twice back-to-back before use
  • Black or discolored water: do not usecontact a service professional

Annual Maintenance Calendar

Field Notes

Things worth knowing

01

Use unscented liquid chlorine bleach at 1/4 cup per 15 gallons of tank capacity. Scented or colored bleach leaves residue. Fresh Citrus is not a sanitation agent.

02

Run the bleach solution through every faucet — hot and cold — and the outdoor shower if you have one. Standing water in low-use lines won't get sanitized by filling the tank alone.

03

Your nose is the final quality check. If your water smells faintly of chlorine after the final flush, keep flushing. You'll taste it in your coffee and it's not worth rushing.

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