Core • Module 2
Module 2 — Equipment & Chemicals: WFP/RODI Equipment Basics (Lesson)
Module 2 — Equipment & Chemicals: WFP/RODI Equipment Basics (Lesson)
What you’re doing today
You’re learning the WFP/RODI stack at a practical level: what it is, what the parts do, and what actually matters on the job.
Why this matters
WFP/RODI wins on:
- safety (less ladder)
- consistency
- premium positioning
But only if your water is actually pure and your technique is clean.
Tools & materials (minimum viable)
- TDS meter (non-negotiable)
- A basic RO/DI system
- A water-fed pole (WFP)
- A clean brush + good rinse technique
The one number that matters
TDS is the scoreboard.
If you can’t measure it, you can’t manage it.
Step-by-step: WFP/RODI startup check (foreman routine)
- Check source water connection.
- Check your TDS reading (in → out).
- Flush/prime as needed.
- Inspect brush and jets (clean, no grit).
- Clean top-down with good rinse discipline.
- Do a final rinse pass.
Decision points
-
If TDS is high:
- stop and fix water quality before doing “spot-free” promises.
-
If windows dry with spots:
- it’s usually water quality, technique, or frames leaking contaminants.
Common mistakes + fixes
-
Mistake: skipping TDS checks
- Fix: treat TDS like fuel gauge.
-
Mistake: blaming the customer’s glass
- Fix: confirm water quality + technique first.
What good looks like
- Consistent spot-free dry
- No ladder required for standard second-story glass (where feasible)
How to prove it (Proof Pack)
- before/after of a representative window set
- note: "WFP/RODI used" + any limitations (sun, heavy contamination)
Do this next (assignment)
- Take 3 TDS readings (tap, post-RO, post-DI) and write them down.
- Clean 2 windows and verify dry-down.
References (SOPs)
- RO/DI overview: 04_sops/windows/ro-di-water-system.md
- RO/DI build SOP: 04_sops/windows/ro-di-system-build-sop-v1.md
- WFP SOP: 04_sops/windows/wfp-window-cleaning-sop-v1.md
Printables
- Operator Checklist Pack (truck copy): 03_curriculum/printables/operator-checklist-pack-v1.md
Field Guide & Interactive Calculator (tbsoftwash.com)
🧪 Interactive Soft Wash Ratios, Pump TCO & Compliance Guides:
Gear Box (Amazon)
Essential Truck Safety, PPE & Chemical Delivery Loadout
- 3M Half-Face Respirator 6300 + 3M 60926 Multi-Gas/Vapor & P100 Cartridges — non-negotiable respiratory protection for SH and acid work.
- 3M Splash-Proof Safety Goggles + LANON Chemical-Resistant Nitrile Gloves + FROGG TOGGS Chemical/Rain Suit.
- XTRATUF Men's 6" Ankle Deck Boots / Dunlop Chesapeake Steel-Toe Waterproof Boots.
- Delavan 5850 5.0 GPM 12V Diaphragm Pump + General Pump 100776 High-Draw Downstream Injector + X-Jet M5 Nozzle.
- 0-14 pH Test Strips + Arm & Hammer Baking Soda (5 lb) — verifying neutral pH on spills and acid work.
- GigaTent Pop-Up Pod Portable Changing Tent — emergency truck-side changing privacy and shade.
Disclosure: As an Amazon Associate, we earn from qualifying purchases.
🛡️ Module 2 Safety Gate — Chemical Safety, SH Ratios & Delivery Systems
Safety Gate Check
Pass this quick operator knowledge check (80%+) to verify SOP mastery and unlock your track certification.
1. CRITICAL SAFETY RULE: What happens if Sodium Hypochlorite (SH / bleach) is mixed with an acid (such as Oxalic or Muriatic acid)?
2. If your tank holds 12.5% Sodium Hypochlorite and you batch-mix a 50/50 ratio with water, what is your approximate roof mix strength?
3. Why does a standard high-draw downstream injector typically deliver ~0.8%–1.5% SH at the tip?
Select an answer for all 3 questions, then click Verify Answers.