Harman PF100 Pellet Furnace- constantly blows- often cold

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New Member
Nov 12, 2021
Western Massachusetts
We have a Harman PF 100 Pellet Furnace installed in 2005. We bought the house 2 years ago and this is our second heating season. The furnace is a workhorse, but we are still learning. We had it cleaned by a local person who came highly recommended. There was very little ash after our first season using it and NEVER cleaning it. We used Woods and Sons pellets and were very pleased. This year we bought Home Depot pellets and the furnace is working overtime blowing cold air. The blower never seems to shut off. After about 7 weeks of use we cleaned it out and got a significant amount of ash. The cleaning did not help with the constant blower issue. Can anyone tell us what we should be checking or doing to figure out why it continues to blow air even though it is not heating the air? Thanks


Minister of Fire
Aug 22, 2010
Northern Canada
Why did you change the pellet supply?
I have heard that there is a big difference in pellets.Some are just inferior and produce a lot of waste(ash, clinkers,ect)
It could be the HD pellets fit into the inferior catagory