Heat Exchanger

[Robzheat]

I have a Harman XXV Pellet stove, and my question is, does the soot and ash build up on the accordian heat exchanger reduce the amount of heat that is generated. I know if it builds up too much it acts as an insulator, but to what extent??

 

[Corie]

I don't have a percentage for you, so hopefully that's not what you're hoping for. Serious ash accumulation will have a pretty profound effect on the heat transfer of the heat exchanger. That doesn't mean that your stove will literally stop putting out heat because of ash accumulation, but it will reduce the heat transfer efficiency. Since its pretty simple to pull down those covers and scrape/vacuum the channels out, you should try to do it often. What makes ya ask?

 

[Robzheat]

How do you pull down the covers on the Harman XXV

 

[Corie]

I'm sorry, I got the XXV mixed up with the accentra. The accentra has cast iron panels that cover the heat exchanger, but the XXV doesn't. All you need to do is scrape that accordian down and you're ready to roll.

 

[jtp10181]

I had a customer that left that part of cleaning the stove neglected for a few years. She was complaining that the flame was lazy and sooty. After she finally realized she had to remove the top baffle and get all the ashes out she said it worked like brand new again.

 

[GVA]

I have a Harman XXV Pellet stove, and my question is, does the soot and ash build up on the accordian heat exchanger reduce the amount of heat that is generated. I know if it builds up too much it acts as an insulator, but to what extent??

Why do you ask?
And like JTP said the airflow in the stove gets choked off resulting in the lazy sooty flame... Especially those that have a panel covering the heat exchanger.
How often did you clean it last season and how many tons did you burn?

 

[Robzheat]

I used about 3.5 tons. I probably cleaned it every 2 days, that was the bulk of my cleaning for the year, keeping the exchanger clean