Danny Moore Hoshizaki America, Inc. Volume 125
Editor 618 Hwy. 74 South January 16, 1996
Peachtree City, GA 30269
Care Facsimile: (800) 843-1056
There are many different types of water treatment
systems available today. Due to the increased concern
over the quality of water, Reverse Osmosis " R O "
systems are more prevalent.
An RO system produces almost pure water with a pH
well below 7.0. This water has been forced through a
membrane under high pressure. The membrane serves
as the filter media and has a pore size in the sub micron
range. Due to the small pore size, the amount of water
that will pass through the membrane is reduced. The
rejected water is flushed down the drain. A ratio of
three gallons of waste water to one gallon of processed
water is common in producing RO water.
As the water is forced through the membrane, solids
larger than the pore size are deposited on the membrane
surface. At some point , the membrane surface loads
up with solids and must be cleaned or replaced. In
areas with a high mineral content in the water, more
frequent cleaning is required. The final purity of the
processed water will depend on the quality of the
system and how well it is maintained.
The water produced by an RO system is extremely
aggressive and is considered an active solvent. The low
pH makes it highly acidic. RO water will attack most
metals and plated surfaces. The RO process increases
the galvanic action of the water which will shorten the
life of rubber parts and can cause plastics to weaken.
As you can see, this could cause problems in an ice
Due to it's aggressive nature, Hoshizaki America
Inc. does not recommend the use of RO water in
our ice machines. If RO water is used the following
damage could occur : Over a period of time, RO water
flowing down the center of a KM evaporator could
wash away the copper/stainless bond and cause
separation of the evaporator plates. If RO water is used
in a flaker, premature bearing wear and damage to the
mechanical seal could result. Other ABS and rubber
parts could also be effected. Any failures caused by RO
water would not be covered by warranty.
Care should be taken in explaining the effects and
discouraging the use of RO water in ice machine
applications. Please advise any customers now using or
planning to use RO water with Hoshizaki ice machines
of these possibilities.