Harman advance not controlling temperature properly

[Davinjw]

hello again,

I’ve been having some issues with my Harman Advance stove. The temperature dial appears to not work correctly...

Often times at night we turn the temperature down to 55-60 to keep the house cool while we’re sleeping. During last season I damaged the exhaust probe and caused shutdown problems (stove would take many hours to shut down). After replacing the exhaust temp probe, the stove will shut down quickly if I turn the stove to “off”, but in room temp mode it’s not keeping temp well. Sometimes set at 50* it will hit 80* in the room, it seems the higher I turn the temp knob the closer to that temperature the stove will stay. 70* works great, until the weather outside warms up during the day.

In any case the stove has only shut down I think once in the last few months. It is definitively in auto mode. We have been turning the room/stove knob to “off” each night and to “room temp” mode each day, and it starts and stops as it should besides running the entire time it’s in room temp mode.

I’ve replaced the room sensor, exhaust probe, and possibly unrelated last season I replaced the exhaust fan and exhaust fan blade (had to cut the old one off). Sourced the parts from amazon using harman manual part numbers.

 

[rickwai]

There are only 3 components that control temp on the stove and you replaced 2 on them. If you are confident that the room sensing probe is good sounds like you have a board problem using process of elimination.

 

[Davinjw]

That actually something I was curious about. Is there any way to test the room temp probe? I’m assuming it’s either an RTD or a thermocouple, in either case most of the time there is a testing procedure as long as you can identify what type. I wasn’t able to find any information on them.

 

[bags]

That actually something I was curious about. Is there any way to test the room temp probe? I’m assuming it’s either an RTD or a thermocouple, in either case most of the time there is a testing procedure as long as you can identify what type. I wasn’t able to find any information on them.

The room probe like the ESP are both some type of thermistors. A thermocouple produces voltage which these don't. They just do resistance with temp change. I imagine a multimeter could check for ohms but what they should read is the question. I guess people just replace them because it is quick and easy. That said the ESP probes in a Harman is a racket for what they charge because when I replaced one in my OWB it was $17 bucks and looked just like the ESP probe in my Harman. about the exact size and length too. It would be nice to know the values and get the same thing cheap from Grainger or some supply place instead of chumping up and taking it on the chin for the ESP $$$ probe. Hell, I paid $17 bucks at a Woodmaster dealer for that replacement probe so I'm sure they are very cheap.

Haven't messed with mine on my Harmans, but I did have one go bad in my Woodmaster OWB. The ETC on it throws a P1 code which identifies the probe. It is a simple little thermistor probe that slides into a sleeve at the rear of the water jacket to send the water temp. Basically the same thing as the ESP on a Harman. The room temp probe is just a smaller version tucked into the end of the wire.

Maybe you can find something Googling testing thermistors but finding what you are specifically asking for it is doubtful you will find much. Every thermistor is different or specific. Finding the Harman probes and verifying readings is probably a reach let alone the spec'ed parameters of operation. It would be nice to know because I know Harman doesn't make these but just use an off the shelf or out of the parts bin probes from some electrical supplier. Then they put a huge premium on them. The room probe might be made specifically for Harman by some manufacturer but still wouldn't take big money to make nor buy if you could find out who and what. It would be nice to know especially for the ESP because they tend to go more often because of the heat extremes I'd guess. I got 10 years out of the water jacket thermistor in the Woodmaster. It would not surprise me if that one and a Harman ESP are the same but I have no idea. We need an electrical components guru here. ANYONE????

I also say this because some have figured out the room distribution blowers on some Harmans are an off the shelf Dayton Blower snatched up at the local Grainger for much less that bolt right up.