Review:
Plumbers
Water Conditioning Licensing
Water conditioning license basics
What is water conditioning work
a single-family residential unit, which has been initially established by a licensed plumber, and does not involve a direct connection without an air gap to a soil or waste pipe; or
a multifamily or nonresidential building, where the plumbing installation has been initially established by a licensed plumber. Isolation valves are required for all water conditioning installations and must be readily accessible.
In multifamily or nonresidential buildings, water conditioning does not include:
a valve that allows isolation of a water conditioning installation;
piping greater than two-inch nominal pipe size; or
a direct connection without an air gap to a soil or waste pipe.
Anyone licensed by the Minnesota Department of Labor and Industry (DLI) as a plumber can perform water conditioning work in Minnesota without obtaining a separate water conditioning license.
You can perform water conditioning work in Minnesota if you are:
You can perform water conditioning work without a license if:
You are registered with DLI as a registered unlicensed plumber or registered unlicensed water conditioner.
Your work falls under the scope of the work your employer is authorized to perform.
Your work is always directly supervised by a licensed journeyworker or master plumber or water conditioner journeyworker or master.
Have at least six months (875 hours) of practical experience performing water conditioning work as a registered unlicensed water conditioner or registered unlicensed plumber. Your work experience must include the following minimum number of hours in these areas:
Installation: 100 hours
Servicing: 200 hours
The remaining hours may relate to any other aspect of water conditioning work; or
Have water conditioning work experience outside of Minnesota, which DLI has determined is substantially equivalent to work performed while in the employ of a licensed contractor in Minnesota, or
Have water conditioning work experience in the United States military, which DLI determines is equivalent to work performed in the employ of a licensed water conditioning contractor. Military work experience must be certified by the military.
Were registered with DLI as a registered unlicensed water conditioner while performing water conditioning work in Minnesota.
Were employed by a company that was licensed by DLI as a plumbing contractor or water conditioning contractor, or registered with DLI as a registered plumbing employer.
Have sufficient work experience from another state as described above and certified by the employer in the other state(s).
Apply online and pay the $50 exam fee.
When approved you will receive instructions about how to schedule your exam.
Complete four hours of DLI-approved continuing education (at least two hours must pertain to the State Plumbing Code and two must pertain to technical topics related to water conditioning).
View information about how to look up your continuing education status
Submit the $53 renewal fee. A late fee of $20 is added for late renewals.
Access iMS to begin the license application or renewal process
Application fee - $50
Renwal - $53
Late Renewal - $73
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