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Hobby Boiler info:

Important notice: Because doing a cold water hydro on our pre-certified boilers can cause harm, Kitsap Live Steamers will no longer preform the hydro test as part of our annual live steam engine self test.

Below are copies of the forms that are used at KLS and accepted by Washington State for checking hobby boilers so that the owners of hobby steam engines can operate them in the State of Washington. Please note that I am not aware of anyone that will certify a hobby boiler for use in the State of Washington. The owner needs to prepare the paperwork themselves and make an appointment with their local boiler inspector to have it certified. Follow the instructions that follow to accomplish the certification:

The process that the boiler owner needs to follow is to first complete the forms and do the boiler calculations. The document "Miniature Hobby Boiler Guidelines" has the information you will need to do this. Also see the sample document: "Sample of a completed form to prepare for boiler certification" which is a sample of a form that was used to certify the hobby boiler on my Pacific. Then the "Boiler form to be completed for hobby boiler certification" needs to be filled out. This is used to record the the information that needs to be completed and made available for the state boiler inspector. All of these forms can be downloaded to your computer by clicking on form.

Once the forms are completed, contact the local boiler inspector for the State of Washington for an appointment. Contact Mike Carlson at 360--902-4983 to find out the contact information for your local inspector. Ask the local inspector for their contact information so that you can send them copies of your documents prior to the inspection date. When the inspector arrives, you will be asked to fill the boiler with water until it is completely full. Then you will need to pressurize the boiler with a suitable pump and pressure gauge until it reaches 1 1/2 times the calculated Maximum Allowable Working Pressure based on your calculations. If it is not a new boiler, it will be 1 1/4 times the MAWP. If your pressure gauge is less than this pressure, be sure and remove it before doing this. Then you will need to fire up the boiler so that the inspector can check to see if the safety valve(s) release at about 5 psi under the MAWP. If two valves, which some tracks require, one should release before the second, usually a 5 psi difference. The boiler inspector will give you the boiler number and you will be billed for this service. Once the bill has been paid you will receive the certificate for this boiler. 

Based on the current code, once you have the hobby boiler certified, you are not required to have it inspected again by the state. However, most model railroad clubs require you to show that you have proof of a current self test of the boiler to run on their track. Kitsap Live Steamers in Port Orchard, WA, Great Northern and Cascade Railroad in Skykomish. WA as well as Train Mountain Railroad in Oregon are examples. 

I, Ken Olsen, can be reached by email at

KLS Boiler Check and Witness Form
2010 ASME Boiler & Pressure Vessel Code Sec 1 (Washington State #70.70.070)
ASME Boiler & Pressure Code Section IV 2007
Miniature Hobby Boiler Guidelines
Boiler form to be completed for hobby boiler certification
Sample of a completed form to prepare for boiler certification
Washington State Boiler Code 2018

Other information on hobby boilers that may be of interest:
Firing up a Steam Locomotive
Running a Live Steam Locomotive
LSB 8000 Instructions
Live Steam Boiler Treatment
Safety Valve Cleaning by SuperScale
Super Scale Safety Vales setting
Site Glass Tutorial
Reference book: "The Backyard Railroader: Building and Operating a Miniature Steam Locomotive" by Jeff Frost

As of December 2018 the following members are authorized to witness boiler checks:

            Don Deffley

            Ken Olsen (Email:

            Ted Karanson

            Tom Huffman
Bill Hartung

    Russ Noe
            Christoper Brew
            Dennis Weaver

Live Steam Locomotive Owners 

Check out this guy's boiler problems: 

Forms for New Boiler Inspections:
Boiler Calculation Report
Miniature Hobby Boiler Guidelines
Boiler report for Ken's Pacific