15
Guide to Warewashing & Janitorial Equipment
Dump & Fill vs.
Overflow Machines
While many operators focus on external specs like size and racks per hour, the internal
wash method of a dishwasher significantly impacts performance, water and chemical
usage, and cleanliness. Commercial dishmachines typically follow one of two designs:
Dump & Fill or Overflow. Understanding the difference between them is essential to
choosing the model that aligns with your cleaning standards, resource efficiency goals,
and maintenance expectations.
Dump & Fill Machines:
Maximum Freshness, Cycle by Cycle
01
As the name suggests, Dump & Fill machines fully drain (dump) the wash water at the
end of each cycle and refill the tank with fresh water mixed with detergent. This design
ensures that each cycle starts with a clean wash environment, which is particularly
advantageous in operations with heavily soiled wares or when food safety standards
are a top concern.
Key Characteristics:
Fresh wash water every cycle
Less potential for soil redeposit on dishes
Typically found in undercounter and door-type machines
May use more water overall depending on cycle frequency
Pros:
• Higher hygiene assurance
— ideal for healthcare,
high-end restaurants,
and allergen-sensitive
environments
• Easier troubleshooting of
water clarity or cleanliness
issues
• May allow longer intervals
between tank cleanings
Cons:
• Higher water consumption
• Slightly longer cycle time
to accommodate draining/
refilling
• May have a higher
operational cost in areas
with expensive water and
sewer rates
Best For: Operators who prioritize pristine results, frequently change out their wash loads,
or have heavy soil that requires consistently clean water to ensure foodstuffs are removed
with every cycle.