arnash said:
As for the warning "Caution: Do not connect to any air distribution duct or system", it treats the reader like he's brain-dead and doesn't have the intelligence to ask "Why?" much less understand the answer. Not a word of explanation, limitation, or qualification. It's so great to be treated like a stupid child. I sense lawyers behind most product warnings, not engineers only, and what's the word that fits many of them? Oh yeah, Boilerplate. And how about the warning that the "use of any replacement parts not recommended by the manufacturer is prohibited" don't manufacturers only recommend the parts that they use and SELL?! Do they really recommend parts from competitors if they pass muster? Have you ever heard of a auto manufacturer or car dealer repair garage doing that? I think not. But don't forget that the Chinese are turning out counterfeit parts for all kinds of things. Buyer beware.
My Lopi has output temperatures in 400 degree range on the highest settings. Think about all the clearances listed on your stove, especially in front of the stove now picture ductwork in the house and things that might be over heater ducts. Imagine a toddler plopping his naked but down onto a 250 degree heat register. Many houses use wall studs and floor joists as part of the ducting. What is the high limit for such non-metal ductwork? I have nary a clue but I bet your pellet stove output temperature exceeds it.
Sure, you can rig up your own system and keep the system at safe temperatures but what happens when your system fails? What turns the stove off if the temperature at the heat registers could potentially be excessive.
Nothing. That is the reason the manufacturer tells you not to hook the stove to the ductwork of the house.
In reality the danger factor is low but I feel it's reasonable for the heater manufacturer to place that sentence in their installation manual as a suggestion to the reader and to cover their butts.