We have a Harman P38 that was purchased just last winter. Occasionally a problem came up and the stove would not burn right at higher settings. It was most noticeable on turbo where it would start building a good flame but then stop feeding until the flame had dropped down very low and then it would start feeding again. At those times the stove had to be kept down around a 3 or 4 setting. Completely cleaning the stove and ESP didnt appear to always help. A couple times the problem just went away on its own and it started burning fine again the next day. The stove has an OAK and was vented with no vertical rise, if that has any effect. Can an ESP or circuit board problem come and go?
Problem with Harman P38
- Thread starter Nick857
- Start date
-
Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.
We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.
We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil. -
Super Cedar firestarters 30% discount Use code Hearth2024 Click here
- Status
Unless you are going to have a service tech come out and correctly identify the failing item, I would start with the ESP probe as it will be the cheapest and easiest to replace (around $40). The ESP can give false readings to the board if it is having problems. The false readings can cause erratic behaviour. As I was reading your post, my first thought was the ESP might be dirty, but you say you have cleaned it. Don't use emory cloth or any rough abrasive on it though.
The probe is a thermal resistor and you could probably measure the resistance across the probe using a multimeter. I know that at zero degrees the probe should have 0 resistance. However, I don't know what resistance readings you should get at other temps.
The probe is a thermal resistor and you could probably measure the resistance across the probe using a multimeter. I know that at zero degrees the probe should have 0 resistance. However, I don't know what resistance readings you should get at other temps.
it also could be dialing itself down.. on turbo if the exhaust temp gets too close to (i think) 480 deg, it will stop feeding untill it gets away from this overheat situation. I had one of those, and those things do rip on turbo. usually, however, cleaning off the probe and the venting takes care of most issues with the harmans.. ash is a wonderfull insulator, and a good coating of it on the probe or in the vent can lead to a misleading esp reading.
I guess if it act up again this winter we will just have to get the dealer to look at it. Even with the few problems the P38 did more than we ever thought it could. The main propane furnace was only used about 12 hours over the entire winter and the ventless heater was only used to help on cold days in a room that has 8 old large windows. Burnt just over 5.5 tons.
- Status