3M STM150 User Manual

To reduce the risk associated with property damage due to water 
leakage:
 • Installation must comply with existing state or local plumbing codes;
 • Read and follow Use Instructions before installation and use of this 

system.

Congratulations on your purchase of the CUNO Foodservice ScaleGard

™

 

PLUS 2 water treatment system. The ScaleGard PLUS 2 systems utilize 
some of the world’s most advanced scale and corrosion control tech-
nologies in a compact, highly efficient package.  
The ScaleGard PLUS 2 system is designed for food service equipment 
with low water draw such as steam kettles and tables, combis, electric 
and gas steamers, misters or other applications, where water consump-
tion does not exceed 6 gph (22.7 lph) continuous. See estimated water 
production chart below. 

The ScaleGard PLUS 2 STM150 is recommended where a minimal 
TDS level is required for proper equipment operation. The ScaleGard 
PLUS 2 TSR150 is recommended for applications where zero hardness 
is required such as proofing ovens, flash steamers, injection steamers 
and misters. 

Before beginning the installation, take a few minutes to familiarize your-
self with the system by reviewing the entire installation, operating and 
maintenance manual.  It is also important to review the criteria below 
to make sure that the requirements have been or will be met when the 
installation is complete.  Be sure to confirm that the feedwater falls within 
the limits shown below.  If you’re not sure if this has been done, check 
with your distributor before installing the system.  This is important 
because failures caused by water related problems are not covered 
under the system warranty. 

Feed TDS   . . . . . . . . . . . . . . . . Up to 2000 ppm (mg/L)
Hardness*   . . . . . . . . . . . . . . . . < 10 grains (171 mg/L)
Iron (Fe) . . . . . . . . . . . . . . . . . . < 0.1 mg/L
Hydrogen Sulfide . . . . . . . . . . . none allowable
Feed pH . . . . . . . . . . . . . . . . . . 4-11
Free chlorine  . . . . . . . . . . . . . . < 2 mg/L
Manganese(Mn)   . . . . . . . . . . . < 0.05 mg/L 
Turbidity . . . . . . . . . . . . . . . . . . < 5 NTU

* Note: For waters over 10 grain hard, a CUNO water softener is recommended 
for pretreatment. Consult CUNO technical services for correct sizing.

Confirm that transformer is compatible with available electrical power 
supply.

 

CAUTION