Module 5 — Windows: WFP (Pure Water) + RO/DI Basics (Lesson)

What you’re doing today

You’re learning the WFP lane: when it wins, when it loses, and how to run it so the glass dries spot-free.

VIDEO: https://www.youtube.com/watch?v=GNkP5djASNc | Water-fed pole window cleaning example (real jobsite). VIDEO: https://www.youtube.com/watch?v=1f6NJuUiWpU | Short WFP clip (Gardiner). Watch brush control + rinse.

Why this matters

WFP wins on:

• safety (less ladder)
• consistency
• premium positioning

But only if your water is actually pure.

Tools & materials (minimum viable)

• TDS meter (non-negotiable)
• RO/DI system
• WFP pole + brush

Step-by-step: WFP startup check (foreman routine)

1. Measure TDS (in → out).
2. Flush/prime.
3. Inspect brush (no grit).
4. Clean top-down.
5. Final rinse pass.
6. Verify dry-down.

Decision points

• If TDS is high:

  • stop and fix water quality before promising spot-free.

• If frames bleed oxidation:

  • switch method or set expectations.

Common mistakes + fixes

• Skipping TDS checks

  • Fix: treat TDS like fuel gauge.

• Not doing a final rinse pass

  • Fix: rinse discipline is the product.

What good looks like

• Consistent spot-free dry
• Less ladder risk on standard second-story exteriors (where feasible)

SOPs

• WFP SOP:
• RO/DI build:
• RO/DI overview:

Do this next (assignment)

• Record 3 TDS readings (tap, post-RO, post-DI).
• Clean 2 windows (shade + sun) and verify dry-down.

References

• Hard water/minerals:
• Oxidation risk:

Printables

• Operator Checklist Pack (truck copy):

Gear Box (Amazon)

(Insert the relevant Gear Box module for this lesson here.)

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