Harman PF100 Help/Troubleshooting

[smellysmells2]

I have a year and half year old Harman Pellet stove, which until recently heated my home like a champ. About a week ago the furnace stopped being able to get my house to temperature. Thermostat was set at 70 and the house was 48. Blower will come on for short periods of time and then turn off without really putting much heat out. Then it will be off for 10 to 15 minutes and turn back on for about a minute or two. This is in contrast to earlier where the blower would run continually (or pretty much) until the house reached the desired temperature. My pellet use was been drastically reduced, so it doesn't really seem like the furnace is really trying to put out more heat.

I called the dealer, who came out and told me nothing was wrong. He told me my house is too big for the unit (about 2000sq ft.) The unit is still under warranty, but my dealer refuses to admit anything is wrong with it. I know how this furnace used to work even on the coldest days and my house was always within 1 degree of my thermostat setting.

So far I have throughly cleaned the unit, replaced the fan limit control switch, replaced the thermostat, replaced the ESP sensor and replaced the main control circuit board. Seems to have gotten a little better, but it is definitely not functioning like it used to. The flame seems fine. Anybody have any experience or thoughts of what could be going on? I am stumped.

 

[wil lanfear]

If you are using less pellets and not getting the heat needed, sounds like that you should turn the feed rate up or maybe a partial bridging of pellets in the hopper.

 

[rickwai]

sounds like a restriction in the hopper/ feeder. With stove cold turn it on to start up. Auger will run for 1-2 minutes or so. Once auger turns off open the door and see if pot is full of pellets, if it is not you have a pellet restriction.

 

[Ejectr]

Take the end cover off that encloses under the pellet hopper and see if the small, round air inlet door is free to move. Sounds like it may be stuck. Should be free to move on its tabs.

I'd also check to see if the burn pot has too many fines in it by removing the front cover with the two wing nuts on the burn pot.. Maybe it's full.

If all that is OK, I'd maybe pick on that stack temp unit that turns on the blower. Sounds like it may be sticking.

 

[chken]

...I called the dealer, who came out and told me nothing was wrong. He told me my house is too big for the unit (about 2000sq ft.) .

What is wrong with the dealer? Didn't he sell you the unit? Why didn't he tell you your house was too big for it when he sold it to you? Then to tell you nothing is wrong, knowing that the unit heated your house just fine, is ludicrous! Why do dealers lie in the direct opposition to the owners' facts? Do they just not care?

 

[mcmaxx]

Look to see if your flame is lazy, just had issues with my pf100. Was getting half burned pellets, no heat, then flame started to seam lazy so I did a complete teardown even took out the shaker chains, ran brushes everywhere heat exchanger, exhaust, even took apart exhaust and ran the shop vac from end to end and there was not to much buildup so looked elsewhere, air leaks, replaced door gasket etc... not it, thought maybe combustion blower but it seemed fine, then one very cold morning as I was outside thought just take one last look at the exhaust one that I just ran a shop vac end to end from inside the house. as I took the end cap off, it seemed to free up the air, pipe was spotless inside looked at the end cap seemed clogged with carbon started to clean it and noticed the carbon had teeth, yes teeth,possibly chipmunk or something small, it was cooked into the wire in the endcap, that is why the shopvac did not remove it, now the house is very easy to heat the pf100 is like new again.