Harmen esp probe issues

  • 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.

TiffanyDiane

New Member
Apr 9, 2017
6
New york
Hi I'm new here and can't seem to find answers to my issue we bought out house a little over 4 years ago and it came with a harmen p43 last year we had our first issue and figured out it was the esp probe replaced it and it's worked great well our esp probe just went again so I'm just wondering what exactly causes the esp probe to go bad is it a common issue or are we possible doing something wrong
 
It's odd to have it go again so soon after the last one. You can damage them if you ram a vent brush through the horizontal pathway running out to the vent. That can cause the esp to get bent and they don't hold up to that. I clean that passage with a piece of rag tied to a cleaning rod and what I can't push straight through I drag out with a bottle brush. I also clean the esp itself with the bottle brush vs removing it each time.
 
Last edited:
Not a common issue at all with any Harman..
assume you mean the Silver probe " in the exhaust tunnel" and Not the probe that is the black temperature wire
off the back of the stove.

[some people call them both ESP probes...
anyways, I have no answer for a 2nd one going bad...can u tell us HOW you know it's bad/? how you checked it etc..
hopefully others will chime in here..
 
  • Like
Reactions: alternativeheat
It could just be getting dirty. Next time you get an error code, brush it off and clean it with some windex and a paper towel.
 
I've never had the esp get so dirty it set a code, usually fuel consumption goes up. But I clean mine monthly.
 
I've never had the esp get so dirty it set a code, usually fuel consumption goes up. But I clean mine monthly.
Same here.. once a month,.get's bottle wash brushed.. usually after couple months I pull it and wipe with alcohol...but I agree, can't see how it would set a code off by being dirty....some people don't clean the probe but once a year..maybe..
 
If you look at a Harman troubleshooting guide that the dealer has 75% of the problems and solutions will say replace the ESP. With that in mind I suggest that the customer has a extra one on hand along with that little metal screw that holds it in position.
 
You have to wonder how many of those esps really needed replacing though. It's like an oil burner nozzle, it's routine to replace it but how often does a nozzle really need replacing ? Especially given they always look a bit funky after the burner has been so plugged up with soot from not cleaning for three years, the culprit becomes the nozzle when a cleaning would suffice and getting everything burning clean again. Been there done that.
 
My ESP was so dirty is threw an error code. I cleaned it was a brass wire brush and code went away. I have burned about 3 tons between when the ESP error code was displayed and I cleaned it and now and all is well.
 
My ESP was so dirty is threw an error code. I cleaned it was a brass wire brush and code went away. I have burned about 3 tons between when the ESP error code was displayed and I cleaned it and now and all is well.
Clean it once or even twice for each ton burned and you won't have that problem. I've never let my ESP go without cleaning for three tons, ever. I clean it when ever I clean the horizontal pathway, I take a nylon bottle brush to it right in place. One guy here was using a brass rifle bore cleaning brush ( probably a good idea actually).
 
Clean it once or even twice for each ton burned and you won't have that problem. I've never let my ESP go without cleaning for three tons, ever. I clean it when ever I clean the horizontal pathway, I take a nylon bottle brush to it right in place. One guy here was using a brass rifle bore cleaning brush ( probably a good idea actually).
I clean mine once a year also. Surprised to hear that some clean it after each ton. Quality of pellets must factor in some?
 
I clean mine once a year also. Surprised to hear that some clean it after each ton. Quality of pellets must factor in some?
Yes. But if someone's stove throws an ESP error code due to dirt after 3 tons burned, then at what point was the stove running less efficient prior to the code showing up? And would that someone really want to wait till the stove throws a code to clean the ESP ? Especially given that some of us have found a way to clean it without removal. It's a 30 second proposition to do while in the stove cleaning anyway. The ESP lives in a tough spot, any particles of crud headed to the vent are run past it.
 
Last edited:
  • Like
Reactions: jackhammer
Prior to last year we didn't even know about the esp probe so had never cleaned it prior to it going bad. Mistake on our part for not getting to know our tone properly. We had payed a guy to clean do a thorough cleaning this year before use and he did a shot job in my opinion but we've already took it apart and cleaned the probe once this year we only burn about 3 ton a year. The other morning my boyfriend woke up and it was smokey in the house and it was burning funny and throwing the 3 status blink code so we took it all apart and cleaned it.(we were told when we got the new probe last year that it has to be cleaned with a soft cloth or we would ruin it) so we just wipe it down good with alcove on a soft clothand when we started it back up after a nice cleaning it started up but the distribution blower won't turn on and that's whathappened when it went last year. I put it in test mode and the blower kicked right on so idk this is our first pellet stove and honestly we are a bit lacking in proper knowledge do cleaning it we usually vacuum it out one a week or other week bit with a new baby we have neglected the weekly vacuuming but until last year we didn't know anything about taking it out and cleaning it so that's new to us this year
 
When is the last time the full venting was cleaned ( the outgoing pipes and such) ?
 
If you look at a Harman troubleshooting guide that the dealer has 75% of the problems and solutions will say replace the ESP. With that in mind I suggest that the customer has a extra one on hand along with that little metal screw that holds it in position.
When is the last time the full venting was cleaned ( the outgoing pipes and such) ?
About a month ago we took it out and cleaned the probe and everything that's why I'm not sure why it went bad cause it lasted 3 years with us unknowingly not doing proper cleaning until the first one went bad and now we're actually doing more thorough cleanings I'm not understanding why it went bad again
 
Tiffany, did you clean the venting system with a vent cleaning brush is what I am asking ( all the pipes going outdoors) ? Not if you cleaned the ESP, I'm not asking you that. I'm asking about the venting because a stuffed up vent will act much the same as a bad ESP, or could act the same as a bad ESP ( note my punctuation, it helps people understand what is written, FWIW. You might try putting some in your messages too, LOL).
 
Last edited:
About a month ago we took it out and cleaned the probe and everything that's why I'm not sure why it went bad cause it lasted 3 years with us unknowingly not doing proper cleaning until the first one went bad and now we're actually doing more thorough cleanings I'm not understanding why it went bad again
Basically the ESP is responsible for doing many things. It blinks when something is wrong but it doesn't tell you what is wrong and just because it is blinking doesn't mean it is faulty. As a example it can be blinking just because it is dirty so you clean it and see what happens. If it works you fixed the problem if it still blinks you should make sure the whole exh system is clean. If that doesn't help then do a good cleaning of the whole stove. These are steps a owner can do before you call the dealer.
Next I would look at gaskets to make sure you have a sealed unit with no air leaks.. After that I would turn the dial to Test and look at the blinking lights and use them to point to the problem.
I thought I sent copies of the dealers troubleshooting manuel to someone and they posted in in Hearth.com a couple years ago. A Harman is a simple stove and there isn't much to go wrong.
 
Basically the ESP is responsible for doing many things. It blinks when something is wrong but it doesn't tell you what is wrong and just because it is blinking doesn't mean it is faulty. As a example it can be blinking just because it is dirty so you clean it and see what happens. If it works you fixed the problem if it still blinks you should make sure the whole exh system is clean. If that doesn't help then do a good cleaning of the whole stove. These are steps a owner can do before you call the dealer.
Next I would look at gaskets to make sure you have a sealed unit with no air leaks.. After that I would turn the dial to Test and look at the blinking lights and use them to point to the problem.
I thought I sent copies of the dealers troubleshooting manuel to someone and they posted in in Hearth.com a couple years ago. A Harman is a simple stove and there isn't much to go wrong.
When it thew the code we took it out cleaned everything in the stove the probe the pipe that's the probe is in and I vacuumed the east going out of the house as far as it goes it points up.. we didn't take the pipe that goes up outside off well have to do that tonight. We started it back up and it started just fine but the blower didn't turn on we turned it off cause it was a nice day and we wernt going to be home.started it up when we got home it threw a different code (for not starting in the alloted time turned it off then back on and ran but still no blower then after running for a bit it started pushing burning pellets into the ash pan so we just shut it down for the night
 
I bet that vertical section of pipe needs cleaning ( the one that goes up outside). And look close at the termination piece. That often has a screen in it and it could get plugged up. Usually there will be a T outside that has a cover on the bottom ( often an inner and outer cover). Take that off and you should be able to brush right up through it to get all the ash out.
 
I bet that vertical section of pipe needs cleaning ( the one that goes up outside). And look close at the termination piece. That often has a screen in it and it could get plugged up. Usually there will be a T outside that has a cover on the bottom ( often an inner and outer cover). Take that off and you should be able to brush right up through it to get all the ash out.
He just took the outside pipe off and it's not really dirty at all
 
Have you looked at the incoming air side of the stove ? Does it have an outside air kit installed (OAK) ?
 
No we don't have an outside air kit and now that I've looked it up to see what it is am realizing that's what the other hole in the wall is for it looks like they were going to put one in but never did
 
No we don't have an outside air kit and now that I've looked it up to see what it is am realizing that's what the other hole in the wall is for it looks like they were going to put one in but never did
Well I asked because they often have a screen too that can get plugged up if not cleaned now and then. Since you don't have it hooked up it's not that then.
 
this may seem silly or brilliant but it works..[got it from a tip last winter]..

I take a long flexible 4" wide chimney cleaning brush[ the kind u would attach to a drill gun etc] and after removing the outside exhaust bottom cap shown, I brush back towards the stove to the inside..
it's a 90 elbow there and any stuff falls straight down behind the stove as shown.
. I then go from the inside with my long vacuum hose past the ESP probe in the tunnel and suck up the crud that I just pushed in from the outside... this way I know I got the elbow cleaned good without dis-assembling any exhaust piping.
 

Attachments

  • Harmen esp probe issues
    IMG_1839.JPG
    88.9 KB · Views: 341
  • Harmen esp probe issues
    IMG_1841.JPG
    106.3 KB · Views: 280
Last edited:
Anyone in the house have a multi meter and know how to use it ? The ESP should have certain readings in ohms if it's good. If it's bad , well it won't then.