P43 draft

[Mac McIlvaine]

I have had a P43 for about 5 heating seasons. As I've mentioned in other posts, I have replaced the stack sensor several times. I've taken a couple of the bad ones apart and found pretty well burnt innerds.

Being a gadget freak, I happen to have a manometer. So I figure it wouldn't hurt to check the draft and the vacuum in the chamber. What should these measure?

And what's the best place to measure them?

 

[JDenyer236]

If the stove has been burning good then there is really no reason to test the draft. The draft test port is on the left side of the stove. Looks like a pipe plug. I can't recall the number of the top of my head but google for the installation manual. Now with that said I wouldn't mess with the draft setting unless you are having burn issues.

 

[Bioburner]

Page 18 of the manual I just downloaded describes how and when of the draft for the 43,61 and 68.
Good luck. Read and learn before you turn and burn!

 

[SmokeyTheBear]

Page 18 of the manual I just downloaded describes how and when of the draft for the 43,61 and 68.
Good luck. Read and learn before you turn and burn!

More exciting the other way Bioburner .

 

[gfreek]

I have replaced the stack sensor several times.

What is a stack sensor ?? Do you mean ESP??

 

[Mac McIlvaine]

Yes, I referred to the ESP as the stack sensor.

It is burning ok at this point...after replacing the ESP for the 4th time in 5 burning seasons.

I figured it was worth a check to see what my draft is, can't hurt.

When I bought the new sensor, the dealer suggested the the combustion blower might be running slow. I find this curious since electric motors, unless the bearings are seizing or the shaft/impeller rotation is being restricted in some way or, there is a speed control system malfunction, will run at a speed determined by the motor design and the applied voltage.

The vacuum in the combustion chamber should give an indication of this if the motor is indeed having some issue, no?

In the end, since I've found no particular reason for the ESP failures and others have said they've never had one fail, I'm just looking for possible reasons for the failures.

Mac

 

[Bioburner]

The company should be wondering why the failures!? Did they pickup the cost of igniters for at least the first three years of warranty period?

 

[Mac McIlvaine]

The igniter has never failed. Only the ESP sensor. And yes, during warranty they did cover the sensors.

 

[Bioburner]

My mistake. ESP replacement. Still only half a cup coffee Lemon law?

 

[Mac McIlvaine]

I know that feeling...

Works fine otherwise. I'm wondering if the natural chimney draft may be causing excess combustion and smoking the ESR's.

That said, the flame never seems particularly high. I have on occasion had the entire stove be what I perceive as way too hot. In one case, it was definitely a chimney fire and the ESR was toasted.

 

[Bioburner]

Something is way off IMHO.

 

[Mac McIlvaine]

Well, way off? It runs for months with no issue. I'd expect "way off" to be reproduceable.

 

[SmokeyTheBear]

Well, way off? It runs for months with no issue. I'd expect "way off" to be reproduceable.

It is, that is why the sensors go south.


Please remember I am not a Harman or any other stove tech so please take what I am saying below with a pinch or two of salt.

Let's see that thing is in the exhaust stream where it is used to keep the exhaust between 300 and 500 degrees, more likely it is failing because the temperature there is on the high end of things.

This leads to possible low draft conditions in the system due to a number of possible causes.

There is my favorite namely crud in the works.

and bringing up the rest of the pack,

we have a bad run of esps, a slow exhaust blower, a screwy control board, and venting issues in no particular order.

 

[PJPellet]

Something is definitely wrong. Your dealer should be at your house with the Harman Diagnostic Tool to check all of the functions in real time.

I am guessing maybe a bad component on the computer board that is affecting the combustion blower speed, just a guess.

Harman has had some quality issues for sure. The paint on my stove is flaking off after four seasons, but that's for another thread.

I am still on all of the original motors and electronics. I burn about 4 tons a season and rely on the pellet stove 100%. Good Luck.

 

[SmokeyTheBear]

The screwy control board also includes possible esp dip switch setting or another option isn't correct on the control board.

The control board has selectable dip switch settable configuration options to match the controller up with the actual stove parts in the stove it is controlling.

Mismatches kinda mess up how the stove burns, sometimes in ways you would not notice.

A bit of time with a Harman DDM PJpellet has mentioned might just be the ticket

 

[Mac McIlvaine]

I did a deep clean this AM. Then did some testing.

According to the manual, in test mode it is supposed to be ~ -.55" WC and after 2 minutes drop to ~.4.

I get ~ -.8 and drop to ~ -.7

Tinkered with the low draft setting and saw no change when the pot was turned either CW or CCW.

 

[Bioburner]

The pot on my older board on the PC45 does nothing at all as well. When put in the new board I could get the pot turned so low as to get the fire to go very lazy and with soot. I need to get the pot replaced and looks like you may as well.

 

[johninwi]

MAc, i've messed with mine with a meter on the draft motor, i didn't record the high/low of the voltage but it went around 95 vac, intresting part was it wasn't very quick to respond, when droping it was about a volt per second.

As mentioned above, the dip switches, you might look at where each is set and switch the back and forth once or twice, i've had boards with switches that appeared to be set one way until you actually moved them and could feel they were not where you thought.

Can you pull the board and visually inspect it for a flaw where the esp plugs in? cracked solder joint or other oddities