P38 new to me???

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Sbct

New Member
Nov 6, 2021
7
Pennsylvania
[Hearth.com] P38 new to me???
Folks. I bought a used P38 with the circuit board upgrade (see photos). I have been noticing a lot of build up on the glass. I clean it off but it happens again within a couple days. I also usually have a bunch of ash on the pellet pot lip. Usually a couple inches and it is not sooty ash but harder pieces of ash. It is totally ash and not unburned.

I have the room temperature set to 50 (as low as possible) and the feed rate set to 2. It does a good job of holding the shop right at 50 so I am happy there but the large ash build up and the soot on the glass it doesn’t seem like it is burning good maybe??

The chimney is clear (no smoke) which I thought meant it was burning well.

Two questions. Should I adjust the feed rate and how can I extend the temperature probe wire so it is not behind the stove which is right beside the door?

Every time I come in the cold air hits that probe and ramps it up. I would prefer it be in the center of my shop. Not sure if I can just cut the wire and splice it? Didn’t know what gauge wire was in the sheathing. Thanks in advance!! [Hearth.com] P38 new to me??? [Hearth.com] P38 new to me??? [Hearth.com] P38 new to me??? [Hearth.com] P38 new to me???
 
Your feed rate should be at about 3, according to Harman.
You can extend the room sensor wire with 18ga t-stat wire,
but the max length cannot exceed 30'.
The glass is gonna get dirty. It happens.
 
And by running it on low it’ll get dirty faster, also check the burnpot holes, make sure they’re not all full of carbon.
 
Tapping it and scraping won’t get all of the carbon off, I use a pick on mine or a drill bit at least once a month
 
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You can put your stove on a thermostat, and place the thermostat where it won't be subject to air drafts. I run both my stoves off battery operated millivot stats. If you decide to use an external thermostat, you will want to run it in parallel with the room temp probe.

If that thing is idling a lot, you will just plain have more ash on the glass faster than if it were running harder.
 
You can put your stove on a thermostat, and place the thermostat where it won't be subject to air drafts. I run both my stoves off battery operated millivot stats. If you decide to use an external thermostat, you will want to run it in parallel with the room temp probe.

If that thing is idling a lot, you will just plain have more ash on the glass faster than if it were running harder.
I just want to really extend the temperature probe. Can I just cut about a foot below the probe tip and splice thermos wire on and extend it? Is 30’ the most I can extend it like some folks are saying? I don’t have a manual for this stove but I don’t think a manual would matter since it has that upgraded circuit board.
 
I just want to really extend the temperature probe. Can I just cut about a foot below the probe tip and splice thermos wire on and extend it? Is 30’ the most I can extend it like some folks are saying? I don’t have a manual for this stove but I don’t think a manual would matter since it has that upgraded circuit board.
Yes you could use just the last foot of wire as long as the tip is intact. The thermistor is located in the very tip. I suspect that they rate the maximum extension of sensor a bit conservatively like "sell by" dates on foods so you might well get away with 35' if that really helped. I do wonder if having the sensor that far way might create some interesting lag situations in the heating cycle. It would be cheap and easy to try out before committing. It may take some experimentation to find the best location for the sensor.

Hugh
 
Yes you could use just the last foot of wire as long as the tip is intact. The thermistor is located in the very tip. I suspect that they rate the maximum extension of sensor a bit conservatively like "sell by" dates on foods so you might well get away with 35' if that really helped. I do wonder if having the sensor that far way might create some interesting lag situations in the heating cycle. It would be cheap and easy to try out before committing. It may take some experimentation to find the best location for the sensor.

Hugh
I may just temporarily splice before making permanent. Didn’t think of that. Thanks!
 
I may just temporarily splice before making permanent. Didn’t think of that. Thanks!
You're very welcome. It looks like a 50' roll of thermostat wire is just over $11 at the big box stores so not too spendy to for a quick experiment.
 
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