Harman P68

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trucker12

New Member
Nov 28, 2019
11
east coast
Hello and Happy Thanksgiving everyone !! I recently bought a used harman p68 and have been running it about a week tinkering with the thermostat probe for best area so stove works best all around temps in home. I have it in the best working area now. The combustion fan is loud so I ordered a new one which will be in next week. Running in room temp mode I notice that every now and then the convection fan goes up and down every few seconds this happens every few seconds for quite awhile, I'm not sure if this is normal or not but it is very annoying not to mention i'm sure it's not good for the fan motor to do this that frequently. I'm hoping the new combustion fan will help a little will the glass staying cleaner but from what I've read here i'm not going to get my hopes up. When I clean the glass it starts getting dirty within an hour or so, if i can get a couple days i'll be happy. The stove was made in 2005 I hooked up 4" pipe and outside air I hooked the probe halfway down the hallway about 22 feet away. The stove runs and looks great except for these annoyances. The most is the convection fan. Any help will be appreciated thanks.
 
Is the probe on an extension to get it 22' away? Perhaps the connection for the extension, or to the stove is not as tight a desirable and for some reason it was making intermittent connection (music or movie with heavy bass rattling things maybe? ) . Could also be a disturbance in the air flow to the probe which casued fluctuating readings?

Hey, I'm not an expert so I go with the wackiest explanations possible ;).
 
On my P68, if I dial the stove setting to room temp and turn it to max, all the way to the right, the fan gets herky-jerky, sort of stopping and starting. I just back it off a nudge from that spot and it's fine. Or turn it over to stove temp mode where the problem doesn't exist.

On the probe, mine is taped to the wall behind the stove about 3 feet up if that. 22 feet seems like a long run and I'm not sure of any advantage, but it sounds like you spent some time with it so you'd know best.

For the combustion fan, a good cleaning makes a huge difference in stove performance overall. I clean it up with a toothbrush and can usually do it in place, but sometimes I have to pull it off to clean it. My stove is around a 2005 as well, and I am on my second fan.
 
On my P68, if I dial the stove setting to room temp and turn it to max, all the way to the right, the fan gets herky-jerky, sort of stopping and starting. I just back it off a nudge from that spot and it's fine. Or turn it over to stove temp mode where the problem doesn't exist.

On the probe, mine is taped to the wall behind the stove about 3 feet up if that. 22 feet seems like a long run and I'm not sure of any advantage, but it sounds like you spent some time with it so you'd know best.

For the combustion fan, a good cleaning makes a huge difference in stove performance overall. I clean it up with a toothbrush and can usually do it in place, but sometimes I have to pull it off to clean it. My stove is around a 2005 as well, and I am on my second fan.
thanks for the response the connections are good and the way the probe is working seems fine and accurate . I noticed that it does it only when after it's reached max temp and is in the cool down sequence. I have been running the fan switch at about med and when it does it the distribution blower light also goes off and on it's almost non stop about every 2 seconds. If i move it to a lower fan speed it seems worst. I moved it to it's highest setting and it still does it. I guess this don't happen to anyone else so something is not right. hope it's not the control board. I was also reading in the book about the low draft adjustment but from what i'm reading that only affects the combustion motor.