ClearStak is the first EPA approved testing facility for partial thermal storage. Under  ISO-IEC 17025, the testing services offered are: 

 

• Method 28 (Certification & Auditing of Wood Heaters)  

• Method 28 WHH

• Method 28 WHH Partial Thermal Storage

• Portable Particulate Testing 

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 Testing can be performed on the following appliances: 

 

• Indoor and Outdoor Hydronic Heaters

• Pellet Stoves 

• Woodstoves