whats up with btu ratings

[kykel]

I bought the enviro M55 Cast FS. thought it was 55,000 btus. in the paper work there was a small piece of paper with the efficiency rating and the btu was listed as heat output 7,660 to 42,130. I guess im asking what is the difference between input and output?

 

[mepellet]

I bought the enviro M55 Cast FS. thought it was 55,000 btus. in the paper work there was a small piece of paper with the efficiency rating and the btu was listed as heat output 7,660 to 42,130. I guess im asking what is the difference between input and output?

Input = total potential btu content of the pellets
Output = btu content converted to heat the room

Output minus the Input is combustion inefficiency or heat out the vent.

 

[kykel]

Thanks mepellet. Now I get It