Jotul F600 with no baffle and no blanket

[akom]

Hi all, I'm pretty new to woodstoves so this may be a dumb question.

I inherited an F600 and it operates erratically (sometimes it won't get hot unless the ash drawer door is cracked, sometimes it burns great without). It could be the wood I'm using (mixture of oak and cherry, age varies but feels light/dry). Rear top corner temps struggle to get past 400F, usually 200F-300F. It really only gets hot if it's fully loaded with fairly small split wood with lots of spacing in the stack. Every once in a while it'll suddenly get going and I can close everything and even turn the main down, and it will stay happy and hot. I still don't know what's different those times. I cleaned out the stovepipe and it's vented more or less straight up through the roof.

In an effort to figure out if it needs any repair, I noticed that the secondary manifold looked crooked, so I pulled it out. Looking at the diagrams, I appear to be missing the baffles and the thermal blanket. Instead, I have a layer of light-colored fire bricks on top of the secondary manifold perforated tubes.

Is this healthy? I'm fairly confident that the stove has been used this way for years. Do I need the baffle and blanket? Are they mutually exclusive with the bricks?

Photo is with the bricks removed and manifold reinstalled. It still seems to be a bit crooked, though not as bad.



Another question is: Are there any guides on repairing this stove? For example, do I need to use cement on the manifold assembly? I seem to have some old cement along the mating surfaces of the upper and lower halves, and it's breaking off in large pieces.

Thanks!

 

[begreen]

The stove is going to run like crap without the baffle and insulation blanket. All the heat and wood gases are going straight up the flue.

@D. Hermit and @paredown have done rebuilds. Search on F600 rebuild in this forum for past threads. It's not a trivial process.

 

[akom]

Thanks @begreen . Any thoughts on bricks vs baffles+blanket? Maybe I can throw a blanket on top of the bricks?

I went through the rebuild threads and performed a flashlight test. I didn't find any leaks that way.

 

[EbS-P]

The wasn’t there a change of the baffle material on some revision of the F600? Did that change anything else?

 

[akom]

One additional note is that the bricks fit on top of the manifold perfectly (4 rows of bricks plus 1 row of half-width bricks), with maybe 1/8 inch of wiggle room. Their length is also perfect to allow them to join each other perfectly on one of the pipes. Thus I am wondering if they were meant for this stove.

 

[Todd]

I don’t think I’d lay fire bricks on top of those secondary air tubes, it may warp them. I’d either go to a local Jotul dealer and see if they can get you the correct parts or try Woodsman Parts Plus and see if they have the parts.

 

[Todd]

Baffle Plate | Cast Iron | Jotul Stoves | Firelight F600CB

Replacement Baffle Plate made of Cast Iron for the Jotul wood and coal Stoves model Firelight F600CB and may be compatible with other manufacturers

www.woodmanspartsplus.com

 

[Todd]

Insulation Blanket | Jotul Wood and Coal Stove Parts

This is the replacement of the baffle insulating blanket for the Jotul wood and coal models

www.woodmanspartsplus.com

 

[akom]

Thanks @Todd for the links.

Before I start replacing things, I'd like to understand the current configuration, the reasoning behind it, and whether replacement is a substantial improvement.

 

[EbS-P]

Thanks @Todd for the links.

Before I start replacing things, I'd like to understand the current configuration, the reasoning behind it, and whether replacement is a substantial improvement.

It absolutely needs a baffle. The F600 was problematic from the beginning. If I were heating 24-7 with it I would probably not put any money into it. Ok that’s not true is see if I could get a piece of vermiculite and make my own baffle. But that’s as far as id go.

You would be much happier running a New Drolet than a leaky F600.

 

[begreen]

Thanks @Todd for the links.

Before I start replacing things, I'd like to understand the current configuration, the reasoning behind it, and whether replacement is a substantial improvement.

Without the baffle there is no residence time for the wood gases. The unburnt and smoky gases are heading straightup the chimney. Even the original, pre EPA Jotuls had a basic baffle system to improve combustion. Adding the proper baffle and insulation blanket will make a huge, day vs night difference. The stove will burn much hotter and cleaner while consuming less fuel. This will be notable in a dramatic decrease of smoke coming from the chimney and a reduction in creosote accumulation.

After putting in the proper baffle and insulation blanket, the stove will run quite differently. Read up on past thread about proper burning in an EPA stove.

 

[akom]

Makes sense that without a baffle there is no residence time, I'll check EPA threads.

I am wondering whether the bricks serve the same purpose and whether baffles+blanket will be a substanial improvement over the bricks.

Here is a photo with the bricks installed. Note that these have been in use in this configuration for 6-8 years.

 

[EbS-P]

I’d burn it like that. Blanket might help some. I’d try to find a cheap piece of ceramic wool insulation but wouldn’t spend more than 35$. You have run it longer than most have run the F600. Save for a replacement.

 

[stovelark]

The F600 had cast iron baffles and top blanket on top of the cast baffles. I'm thinking you have cooked the top of that stove pretty good, seeing as air flow should be up and around baffles and secondary burn chamber (which needs to be cemented into manifold at back and air tight as possible) to keep the heat in the stove longer and actually garnish the heat of the fire chamber into sides and rear of stove along with top of stove. For best results, the air chamber/tubes, baffles and blanket should be installed, a close inspection of top cover to check its integrity and cement top corners of stove, replace top cover gasket too. The F600 secondary burntube stove was a great heater, long pieces of wood, big firebox (when compared to its predecessor the F12 cat model). Putting bricks on top of the tubes definitely not a good idea. Look in F600 manual for the cast baffles PN's, you'll probably have to get them from a Jotul dealer or Woodman's Parts plus. Good luck with her.

 

[akom]

Thanks for that explanation.

On the parts diagram I see some kind of a frame (part 71) above the blanket... maybe it's a top seal? Trying to figure out if I'll need anything besides the baffles and the blanket.

 

[EbS-P]

Part 71 looks like the top gasket.

 

[stovelark]

Yes its gasket being referenced. Its important this gasket, Firelights had an issue in part of the production run that furnace cement wasn't sufficiently put in place when assembled. These upper corners were a source of leaks at times... an easy fix without tearing stove apart was putting 1/8 or 1/4" gasket in outer seam, pushing it in place. That was a temporary fix, as opposing to taking the top off the stove and re-cementing from inside.

 

[akom]

Quick Update: After a cold month of experimentation, I'd say that the stove is working fine as it is, as long as it is properly loaded. As I'm new to woodstoves, I assumed that piling wood on the grate would provide sufficient airflow, but I seem to have been wrong.

As long as I load using the "Top-Down Fire Building" as indicated in the manual, it works perfectly. Specifically, what seems to be important is building on two logs front to back, and keeping the central front-to-back valley open. As long as the rest of the wood is propped up a few inches and criss-crossed, all is well. I am now firing with the main air control at about 30% open (used to have to have it fully open).

Obviously I cannot say whether the stove would be more efficient with the baffles and blanket, but it's heating the house very well, and I able to keep the rear top corners at close to 400F easily (center top winds up in the 500F-700F range).

 

[D. Hermit]

It absolutely needs a baffle. The F600 was problematic from the beginning. If I were heating 24-7 with it I would probably not put any money into it. Ok that’s not true is see if I could get a piece of vermiculite and make my own baffle. But that’s as far as id go.

You would be much happier running a New Drolet than a leaky F600.

Crazy take in my opinion. F600 is a fantastic stove. I rebuild 5-10 a year for people who are happy to spend a lot on them to get them back in shape and burning like new for another 25 years.

And saying a New Drolet would be better is comparing apples to oranges. Drolets are basically all welded plate steel. Of course there will be less maintance to them, they are completely different styles of stoves.

But cast iron is preferred for many people. More mass and better more even heat.

 

[begreen]

This may be a confusion with the predecessor the F12 which had some issues. The F600 was a solid, big heater.

 

[stovelark]

Absolutely BG. The secondary burn tube Firelight with side door was a tremendous heater, as well as being a beautiful stove. If it had a weak spot, it was folks sometimes trying to get that last piece of wood in from the side door, and prying up on and loosening the secondary burn chamber, leading to issues. If left alone to do their job, that chamber would do well, if the ashdoor was not left open to "get the fire going". Lots of folks made that costly mistake, leading to the lower baseplate cracking. The Firelight 12 stove was a different animal, a good stove if conditions were ideal, good dry wood was used, etc. The F600CB was by far the better version. Keep warm all.

 

[Dexter]

I have an F-12cb (f-600) with which I heat 1800-2000 sq. feet of my house in Boulder County CO. When you use an F-600 24/7, the top plate (which is a 2 piece plate over the burn tubes) tends to warp over time. The expansion would mis-shape the hot air manifold, and the air tubes would fall out. After my second new manifold package, I modified the stove. I believe the previous owner of yours attempted the same type of modification, but probably made mistakes.

In my stove, I removed the warped top plate (burn-plate). I used split fire-brick cut to lie over the tubes, but THEY MUST be held off of the tubes with COLD ROLLED steel dowls (3/16th"). You MUST, use the heat blanket. If you don't have one, get one from Jotul. With this mod, I see my stove burn very similarly to when it was stock, with 8 hour fires (3 hours of visible flame and 4 to 5 hours of "heating"), cruising in the 550 to 600 degree range stopped down about 80%.

This being said, my stove has developed a crack and pretty good air leak at the left rear of the firebox after an accidental runaway from the ash door being left ajar. Pissed me off! (Glad it wasn't worse!) I got the stove in 1999, and now I think I'll get "fusion" (2 gram/hr) stove, probably another jotul.

See if you can find my old thread detailing the mod. (This is my first time on this site in a LONG time).

Best, Dexter

 

[akom]

Thanks @Dexter , I think I found that post: https://www.hearth.com/talk/threads...elight-inside-guts-of-stove.76480/post-969270

Might give that a shot next season.

 

[stovelark]

Not trying to be a debbie downer- but when I hear people doing modifications (and could be perfectly safe), MFR certainly would not sanction this, but I worry more about an insurance company not wanting to do the right thing and insure you if they find out (if you were to have an issue and its related to an appliance) you modified the unit in any way. Don't mean to ruffle anyone's feathers, just being remindful. Stay warm, and safe.