
Summary
And How to Prevent Costly Rework, Failed Inspections & Voided Warranties
Most dish machine failures don’t happen because of poor manufacturing—they happen because of incorrect installation. Utility mismatches, drainage errors, missing water treatment, and improper clearances are the top reasons for re-inspections, shutdowns, and warranty denials.
Below are the most common issues by dish machine type, based on real-world field conditions.
Undercounter Dishwashers — Most Common Install Problems
Used in: Coffee shops, cafés, bars, break rooms, micro kitchens
1. No Indirect Drain / Missing Air Gap
Problem: Machine hard-piped directly into the sewer
Why it fails: Creates backflow & contamination risk
Result: Immediate plumbing code violation
Fix: Install floor sink with required air gap
2. Undersized Electrical Circuit
Problem: Shared outlet with other equipment
Why it fails: Causes breaker trips & control board damage
Fix: Dedicated circuit sized to manufacturer specs
3. No Water Softener on Hard Water
Problem: Lime scale forms within weeks
Why it fails: Heaters burn out early
Fix: Install softener before commissioning
4. Installed Without Clearance
Problem: Pushed tight under counters
Why it fails: No service access = code & warranty risk
Fix: Maintain required side/rear clearances
Door-Type (Hood) Dishwashers — Most Common Install Problems
Used in: Restaurants, schools, catering kitchens
1. Booster Heater Undersized
Problem: Cannot maintain 180°F at peak demand
Result: Sanitizing failure, failed inspections
Fix: Size booster based on rack volume & GPM
2. Power Hose Not Installed
Problem: No pre-rinse spray at scrape station
Result: Grease loads overwhelm wash tanks
Fix: Install backflow-protected spray valve
3. No Condensation Hood (When Required)
Problem: Steam builds up in dishroom
Result: Mold, rust, ceiling damage, inspector citations
Fix: Add Type II condensation hood where required
4. Hand Sink Blocked by Tables
Problem: Sink installed but unusable
Result: Automatic inspection violation
Fix: Reposition tables, maintain 30" clearance
Conveyor Dishwashers — Most Common Install Problems
Used in: Hospitals, schools, universities, high-volume cafeterias
1. Floor Sink Too Small for Discharge
Problem: Wastewater overflows during peaks
Result: Standing water + shutdown
Fix: Properly sized floor sink with strainer
2. Chemical Pumps Not Calibrated After Install
Problem: Incorrect sanitizer concentration
Result: Failed sanitation + toxic exposure risk
Fix: Chemical calibration at commissioning
3. Conveyor Speed Not Matched to Wash Cycle
Problem: Dishes exit before full contact time
Fix: Adjust conveyor speed to manufacturer specs
4. No Utility Isolation Valves
Problem: Cannot safely service machine
Fix: Install shut-off valves at connection points
Flight-Type Dish Machines — Most Common Install Problems
Used in: Prisons, military dining, stadiums, central commissaries
1. Gas & Electrical Loads Not Coordinated
Problem: Gas booster installed without adequate electrical for controls
Result: System will not safely start
Fix: Full utility coordination before setting equipment
2. Structural Floor Load Not Verified
Problem: Deck not engineered for equipment weight
Result: Structural risk + delayed approvals
Fix: PE load verification during design
3. No Lockout-Tagout Clearances
Problem: Emergency stops blocked
Result: OSHA exposure + safety citation
Fix: Maintain required access zones
Low-Temp Chemical Dish Machines — Common Install Errors
1. Wrong Test Strips Provided
Problem: Chlorine strips used for quat or vice versa
Result: Inspector automatically fails verification
Fix: Match strip type to sanitizer
2. Chemical Lines Installed Backwards
Problem: Rinse agent and sanitizer reversed
Result: Dishes look clean but are unsanitized
Fix: Color-coded line inspection at startup
High-Temp Dish Machines — Common Install Errors
1. Incoming Water Not Hot Enough for Booster
Problem: Booster cannot make full temp rise
Result: Final rinse misses 180°F
Fix: Verify actual incoming hot water temp during testing
2. No External Final-Rinse Thermometer
Problem: Staff cannot verify sanitizing temp
Result: Management control violation
Fix: Install external verification thermometer
Universal Installation Failures Across ALL Dish Machines
- No water treatment system
- Missing air gaps
- Improper drain slope
- Machine not leveled
- No PM documentation at turnover
- No staff operational training after install
- No chemical calibration log
- No commissioning checklist
Aldevra Install Best-Practice Standard
A dish machine install is not complete when the machine turns on—it’s complete only when utilities, sanitation, drainage, water treatment, staff training, and inspection readiness are all verified.





