Pacific Energy Spectrum draft issue --- NOT!!!

[kneelh]

Long story.. bear with me , or skip to end.

Purchased first Pacific Energy Spectrum in 1985.. it was baby blue enamel.
8 feet of double wall black into 25 feet of Selkirk chimney.
Used that wood stove for 25 years until we changed decor, so we migrated it to the cottage and purchased another PE Spectrum in 2010.

From day one, I had nothing but problems with it. It behaved 'differently' than my old unit. Would start up incredibly fast and if I wasn't careful, it would 'take off'. It also did not seem to throw the same amount of heat, nor could I keep a fire overnight. The first winter I went through much more wood.

I had installers back to inspect stove, they checked that the baffle was seated correctly (apparently a common issue) and we started it up. They said everything was fine, likely minor changes over the 25 years to the stove's design to meet higher EPA requirements, coupled with a tall chimney, was what I was noticing. Sigh.. I didn't like this new stove. The old blue one still worked wonderfully at cottage, with 12 feet of chimney.

Chatted with nice people at PE about my stove, they suggested the draft was too strong and was sucking the heat off the stove.. good point, and reading different forums, that seemed like the likely issue. So I went out and purchased a flue damper. That sort of helped.. it slowed down the quick heat up for sure, but it's side effect was I was constantly having a stove filled with coals.. it wasn't burning it all up.

Still unsatisfied, I went out and purchased a k-type thermocouple (used for Diesel truck exhaust temps) and hooked it up to a RaspberryPI computer to monitor the actual flue temperature real-time. My intent eventually was to design a mechanical arm that would automatically adjust the air damper as the temperature rose, as I was finding I was always having to adjust the air flow on this new stove. Basically to automate the airflow based on flue temp. Progress stopped when I couldn't figure out the mechanics needed to push the air flow control with a control arm. I did however, every minute, publish to my website, the current flue temperature, which was very handy! Side note: the through-the-pipe stack thermometer I have is incredibly inaccurate compared to the k thermocouple. I was often seeing temp difference of +150c, it is very slow to react.

Fast-forward a few years.. and talking to several chimney sweeps each autumn, most were surprised I didn't like my PE. Nearly all their customers loved theirs. A particularly aware sweep, noticed that my air-punch-out on the back of my pedestal was still in place. Ah-ha, I thought, perfect, that's the reason, it's drawing air from the wrong location. Removed the plate and waited for winter to arrive. Alas, that was not the problem. Still crazy heat temps, low output, tons of coals.

By now, 6 years in, I was starting to grasp at straws to understand why my stove was not right... More reading lead me to believe that perhaps air was coming in around the window and I should replace the gasket. So, yup, replaced the gasket but again, no change in behaviour.

More internet research about EPA wood stove testing lead me to believe that the testing was done in Miami!! With very little draft on the chimney... not sure if I believed it, but it confirmed what others said, the strong draft in my chimney was THE issue. I resigned myself into believing this was just the way it was.

This past summer, decided to sweep cottage chimney myself.(it gets only a couple of days usage a year) Swept the chimney and vacuumed the ash off the top of the baffle. Flushed with how easy it was, decided to sweep chimney at home. After I swept the home chimney I went to clean top of baffle..WHAT THE HECK.. there is NO rock wool blanket on the top of my baffle! I can see metal. It's missing! I ordered the blanket and installed it.
I am just totally blown away.. my wood stove is now PERFECT! It's throwing tons of heat, temperature control is a breeze and no more coals. It's like I have a new stove! Obviously the installers of the wood stove forgot to install this blanket, I am not sure why

Summary- Too long, didn't read:
If your Pacific Energy wood stove is not meeting your expectations regarding heat output and temperature control and you're blaming a strong draft as the reason, check to make sure you have this Ceramic Blanket installed!!
To show you the before and after difference, here is a graph of a cold startup temperature graph.. note the old unit reaches 150 in like 3 minutes, while the corrected unit now takes 15mins!!

 

[jetsam]

Obviously the installers of the wood stove forgot to install this blanket, I am not sure why.

He was insulating his house, one stove at a time.

Congrats on fixing your new stove!

 

[kneelh]

Congrats on fixing your new stove!

Thanks.. it's been 8 long years, to get my 'new' stove!

 

[saydinli]

Nice job finding the issue. I wish my high draft issue was as easy.

 

[MisterFixIT]

Progress stopped when I couldn't figure out the mechanics needed to push the air flow control with a control arm.

Yeah, I thought I would never be able to figure that part out either. But my PE has such a nice long travel (left<->right) air control I kept trying. Then I stumbled on ....

https://openbuildspartstore.com/mini-v-gantry-set/

Added a MotorHat and NEMA17 stepper, etc and done. I still haven't added the limit switches, thats up next. Im sure there are other ways to move the arm like with a threaded rod/lead screw but with the belt/pulley method its simpler to have a manual override.

Here is the build thread.
https://www.hearth.com/talk/threads/wood-stove-automation-using-the-raspberry-pi.166145/

Good for you figuring out the baffle blanket issue.

 

[kneelh]

Re: Automating the air supply: One of my concerns was what happened if the Pi 'froze'? I was thinking I'd have some sort of relay that stayed 'closed' as long as it got a 'heartbeat' from the PI, otherwise the relay would open which would automatically ( via springs perhaps?) close the air supply. Likewise, i was wanting something that would 'go safe' in the event of a power failure.

My setup is similar to the link provided.. great-minds-think-alike I will investigate how they manage the fan speeds, as now I don't have to focus on the air supply side. Thanks!!

 

[Highbeam]

Maybe your string draft sucked the blanket right up!

 

[kneelh]

Maybe your string draft sucked the blanket right up!

Yes, but, the blanket would have stopped at the chimney cap, blocking the airflow, thus reducing my draft?

No, I believe it was installers incompetence.

 

[Highbeam]

Some installers might think they’re doing you a favor by removing that blanket. Maybe they don’t understand the purpose, maybe they assume it will be a problem to leave it, maybe they stole it for another customer, or maybe it was missing from the factory.

Good job getting your stove working better for you. Also good that you can sweep your own chimney.

 

[SculptureOfSound]

Awesome story, and to think one small component had such a huge effect.

I'm curious, did the appearance of the flame/burn change noticeably after installing the blanket? I mean, could you make the flame lazier with air down, or did it burn noticeably different in any way (other than better secondaries) such that the flame actually looked like it was burning with less draft? Or does it look mostly the same but just perform way better?

 

[kneelh]

Or does it look mostly the same but just perform way better?

The flame pattern is significantly different, there is much more 'down' flames coming from baffle, and the wood is now burning from the 'center' now. Before the wood burned from the front and moved backwards, now it's burning from the center and spreading forwards and backwards.

 

[mar13]

Kneelh,

Can you sometime post DIY instructions on creating that Raspberry PI data logger for temps? My wife has one and maybe I can use this to get her to nerd out on wood burning.

Thanks!

 

[Wiess]

This is interesting to read. My stove is new this year, masonry chimney with a 18-20' stainless liner. High winds are common in this area and fuel is mainly fir. I do find it hard to control the heat and the wood is burning front to back, struggle to have coals in the morning. I can see some white insulation near the front of the baffle.

 

[kneelh]

Kneelh,

Can you sometime post DIY instructions on creating that Raspberry PI data logger for temps? My wife has one and maybe I can use this to get her to nerd out on wood burning.

Thanks!

I'll try to put a post together over Christmas, but someone else has also posted about using a PI... see thread linked above.

 

[ratsrepus]

Isnt the blanket supposed to be in the stove when its sold, why would this be the installers fault?

 

[kneelh]

Isnt the blanket supposed to be in the stove when its sold, why would this be the installers fault?

My guess would be the units are shipped 'unassembled'.. with the blankets, baffle and bricks packaged separately and installed in the woodstove at the customers house.

 

[vwmike]

Interesting, I’ve replaced the blanket in two PE stoves, but never realized they make such a
big difference as both stoves I replaced them in where before I started burning in them.

 

[Highbeam]

Isnt the blanket supposed to be in the stove when its sold, why would this be the installers fault?

The installer either removed it or failed to verify its existence. The owner’s manual has installation instructions which identify it.

I don’t use installers but some people have to and depend in them for a thorough job.

 

[ratsrepus]

My guess would be the units are shipped 'unassembled'.. with the blankets, baffle and bricks packaged separately and installed in the woodstove at the customers house.

every stove I have bought in the last 50 years has come assembled. Maybe the fire bricks were seperate. Thats strange

 

[ratsrepus]

I could see them being shipped like that so they dont get tossed around during shipping although

 

[Hogwildz]

The blanket on the A body baffles(which is what you have) is contained with a s.s. heat shield over the top & sides top of it. The shield also keeps debris from settling on the blanket, which I image would be a real mess to try and clean off/out of the blanket. If you don't have the S.S. cover over the blanket, you're still missing a part, the cover. Is is held on by a split tab that slides through a slot in the center of the cover and is bent each way. Here is what it should look like.

PE ships with everything installed with the exception of the brick & the door. Which are boxed separately.
Your installer either does not know these stoves, or negated to install the baffle assy complete, which is how it is made. The blanket & cover did not just disappear. The should have come as an assy, installed in the stove.

 

[kneelh]

fuel is mainly fir. I can see some white insulation near the front of the baffle.

I would expect ( and I'm no expert ) heating with Fir is going to be problematic, as it is a softwood and thus, burns hot and fast, thus might be part of your issue of heat control and no coals in morning. You should lift your stove pipe and verify you can SEE your white insulation on top of your baffle.. perhaps yours is all bunched up in the front?

 

[kneelh]

Kneelh,

Can you sometime post DIY instructions on creating that Raspberry PI data logger for temps?

Here is my sample code for you.. in python.

 

[begreen]

I would expect ( and I'm no expert ) heating with Fir is going to be problematic, as it is a softwood and thus, burns hot and fast, thus might be part of your issue of heat control and no coals in morning. You should lift your stove pipe and verify you can SEE your white insulation on top of your baffle.. perhaps yours is all bunched up in the front?

Lots of people in the west heat with doug fir. It is our preferred wood for this household. It doesn't burn overly quickly in large splits. We get 8-12 hr burns with it depending on how much fuel is loaded and how hard the stove is being pushed. Not sure what species of fir Wiess is burning. My guess would be balsam fir, which may not be a nice to burn as doug fir. In Newfoundland there should be other options that may be preferable.

As noted, on this model the insulation blanket is inside of the baffle, not exposed. The white insulation along the sides of the baffle for sealing purposes.

Wiess Turning down the air sooner and burning larger splits should provide longer burns and more even temps. Do you have a flue thermometer? That can make it easier to determine when to close down the air. The temp will depend on whether this is single-wall or double-wall stove pipe.

 

[Wiess]

Hi begreen - first let me thank you and others for all the information posted on this forum, I am learning a lot. I read many posts on this forum last winter prior to purchasing the Super 27 this summer. We heated with wood for 25+ years with a pre-EPA Drolet and are adjusting our habits.

You are correct, we are burning mostly balsam fir. There is some spruce, larch, and birch mixed in but predominantly fir. These are the available species in my area.

I have started to turn down the air sooner (50% at 250-300ºF, 75% at 350ish) and it seems to help. Depending on the wind speed I occasionally close it completely at 400 stovetop temperature. The secondaries light and stovetop temp will continue to rise, it has reached 800ºF but most times 550-600ºF. I do not have a flue thermometer yet but I will pick one up as I wonder if the high winds are pulling heat up the chimney before the firebox warms up, I have double wall stove pipe.

The wood was cut/split/stacked a year ago. Perhaps some is split too small for the overnight fires, I split it smaller to ensure it was sufficiently dry for the new stove. I do have some larger pieces that I am putting aside specifically for this purpose. I also have some wood stacked outside that I am starting to mix during windy times, it was CSS at the same time but I did not have room for it in the shed.

What is a good temperature on a probe thermometer for the initial air reduction? When would you reduce it again and when to close completely? (Let me know if I should start another thread.)