The EVO Trio product line of boilers from Hamilton Engineering Inc. has an available BTU firing rate capacity from 200,000 Btu to 8 million Btu and operates at thermal efficiencies up to 99.8 percent and combustion efficiencies up to 98.2 percent. EVO is available as a closed-loop heating boiler or a direct water heater. The product line recently passed efficiency and emissions tests related to the upcoming standards changes for 2013 in California.