Jotul F 400 Inspection Cover - EUR vs USA?

[cycloxer]

Can anyone tell me what the difference in operation is between the EUR and USA inspection covers? It looks like the EUR one lets in more air by default through the extra slot. Which one should I use?

 

[Frostbit]

I used the USA plate the first season. I had the same thoughts you did...the EUR plate appeared to flow more air, so three months ago I put it in.

I've run close to a cord of wood through the F400 since, and I believe I'll leave it in. It seems to provide better control of my fire. I am assuming the difference between the plates only reflect the USA EPA's regulations, which quite possibly means the EUR plate is what this stove was engineered and designed to run with.

I could be wrong, but I'm leaving mine in.

 

[cycloxer]

Yeah I am thinking how you are thinking. This Norwegian stove should have the EUR plate in there for optimal performance. I am sure the USA plate restricts more air to meet EPA regs. I tend to burn my stoves medium-hot anyway as they burn your wood better. I'll try out the EUR plate.

 

[polaris]

Mine has 2 bolt holes in the top. One bolt just sits in the second hole to close the hole but does not attatch to anything under the plate. Any ideas?
Joe

 

[cycloxer]

Two bolts secure the cover to the stove. The third bolt extends through the cover and acts as a height restricter to keep the sliding vent in place. The slot in the EUR plate looks like it will let more air into the firebox by default. The USA plate has two smaller cut outs to either side.

 

[polaris]

Two bolts secure the cover to the stove. The third bolt extends through the cover and acts as a height restricter to keep the sliding vent in place. The slot in the EUR plate looks like it will let more air into the firebox by default. The USA plate has two smaller cut outs to either side.

I got ya. What I am saying is I have 4 bolts, one on each side and 2 on top of the plate

 

[cycloxer]

Interesting. I wonder if there was a running design change? What year is your stove? My stove has an Oct. '09 manufacture date and while I have two openings for bolts, there were no bolts in there. I took the whole assembly apart so I know. They also aren't listed on the latest schematic. I'm going to try the EUR cover tonight and see how that runs.

 

[polaris]

Mine has a 08/06 date of man. So you have one bolt hole open? I could reach in and remove the bolt with my fingers. I have taken the cover off every year while cleaning and just dropped it back in while reassembling. Maybe I should just pull it out and toss it. The only reason I haven't is I thought it might prevent a little bit of ash from entering there(not that it would really matter).
Joe

 

[cycloxer]

My USA cover came installed with 3 bolts on the top surface: one on either side to secure it into place and the 3rd longer bolt in the middle w/ a nut. The two openings that face towards the inside of the stove have no bolts in them. The EUR cover also does not have these opening, only openings for 3 bolts. Instead it has a 2" slot cut out in the center. You can see that in the picture above.

 

[polaris]

My USA cover came installed with 3 bolts on the top surface: one on either side to secure it into place and the 3rd longer bolt in the middle w/ a nut. The two openings that face towards the inside of the stove have no bolts in them. The EUR cover also does not have these opening, only openings for 3 bolts. Instead it has a 2" slot cut out in the center. You can see that in the picture above.

Still with ya. The only difference is where you have one hole near the center I have two.
Joe

 

[cycloxer]

Okay. I know on mine the only purpose of the longer third bolt is to hold the sliding vent in position. It just prevents it from moving up and potentially getting jogged out of place. The cutout in the EUR cover must be to let in more air. The only thing I can figure is that this increases combustion such that Jotul couldn't meet US EPA regulations. Personally, I'd rather have the stove configured as it was intended by its designer.

 

[polaris]

I agree. And I think when I get home tonight if the stove is cool enough and I can round up the Euro. one I will install it. Funny, I never really gave it much thought prior to this thread.
Joe

 

[cycloxer]

Well I literally picked up my stove in the box and on the crate from Jotul. I found some interesting things when I unboxed, including a wooden wedge to hold the baffle plate into position during shipping. I can't imagine what would happen if you forgot to remove that thing, hahaha. I searched all the documentation including reading the Euro instructions, but there is no text for this EUR plate. It shows up in one of the figures on the last page of the Euro instructions, but nothing explains what it does.

 

[Skier76]

Same deal here...we bought our stove and hauled it from the store in the crate. I've often wondered if the Euro plate would show any difference in burning.

 

[begreen]

Ran ours for a month with the EUR cover. It seemed to put out a bit better center startup air, but left our glass a bit more blackened. I got the stove for clean burning and a good fire view, so I put the US cover back on and left it that way.

 

[cycloxer]

I swapped it out for the EUR plate. All it does is to let in more air by default which is what I want. The EUR plate has a 1.5" wide center slot. The USA plate has two 3/8" wide slots on either side. I'll try both and see if I can tell a difference.

 

[Frostbit]

There ought to be a whole bunch of extra plates, either or, floating around folks garages. I'll take them off your hands, if they are just taking up space! My take is if the EUR plate was not to be used in the USA, they would either not be shipped with the stove (saves Jotul some money), or the individual US dealer(s) would be told to remove them from the crate before the stove went to its new owner.

All interesting stuff. This is a good read, as others have the same questions. I think my next move will be to take the USA plate with its two small holes on either end and add perhaps three more, same size, across the front for a total of 5. Or, take the EUR plate and put the two end holes in it the USA plate has. I happen to have a set of quality 1/4" high speed carbide burrs and an air tool to accomplish this is short order.

Who knows, may be that a "custom" primary air dispensing plate might be a desireable item amongst the Jotul-mongers!

One other thing, why does Jotul call it an "inspection cover"? It is, basically, an area-specific air dispensing device. The air regulation is done with the lever actuated sliding plate, which you have control over no matter what "inspection cover" you use.

 

[cycloxer]

LOL, I know what you mean. The only way I could inspect anything was to unbolt it. Maybe this is some Norwegian design term that was lost in translation. The way I see it, the plate is the default air intake regulator.

I really like your idea of adding a few holes to the USA plate. My stove is a bit warm right now, but if I remember the dimensions of the cross sectional areas:

USA Plate - two 3/8" dia slots = .28 sq. in.

EUR Plate - 1.5" x 3/8" cutout = .56 sq. in.

So the EUR plate lets in roughly twice as much air by default. You could two more 3/8" dia holes or slots to the USA plate, or customize it as you wanted.

 

[Skier76]

Ran ours for a month with the EUR cover. It seemed to put out a bit better center startup air, but left our glass a bit more blackened. I got the stove for clean burning and a good fire view, so I put the US cover back on and left it that way.

That's good to know. Anyone else using the Euro plate have the same issue with the glass blackening?

Now, if the Euro plate lets in more air, in theory, wouldn't this allow more in even when you have the air control all the way to the left? I know by design, you can't choke the stove down 100%...so even with the air "closed" all the way, air is still going to the firebox. With the Euro plate having a larger hole...I'd imagine more air would be going in even when closed.

 

[cycloxer]

With the Euro plate having a larger hole...I'd imagine more air would be going in even when closed.

Yes, absolutely. If you want to be able to choke the stove down more, use the USA plate.

 

[pmac]

Did the extra plate come with the stoves originally, or did you folks order them afterwards? I bought my Castine about 8 years ago (double door model) and don't remember seeing that. Wonder if it could be bought aftermarket?

 

[Frostbit]

With the Euro plate having a larger hole...I'd imagine more air would be going in even when closed.

Yes, absolutely. If you want to be able to choke the stove down more, use the USA plate.

Hmm. I'm not sure this is correct.

Once that lever is slid all the way left, isn't the floor shutter closed?...meaning no primary air, just the secondaries, which are unregulated?

I sure would like to see an intake air-flow diagram of this stove.

 

[cycloxer]

Okay a few people have asked me about this EUR cover so I put together a picture with colored arrows. With the USA cover in place, you will get air control coming out of the two 3/8" dia slots on the sides as shown by the red arrows. If you switch to the EUR cover, you air will come out of the center as shown by the three blue arrows, roughly twice as much. The air flows from the bottom as shown by the green arrow, regardless of which cover you use. When the air is fully shut off this lower opening is closed. What I can't say is whether any air flows from the sides as shown by the yellow arrows.

 

[Frostbit]

Very nice description..w/graphics, no less!

I still wonder as well about when the air control lever is fully closed (left), just how and where the air flow is then. Perhaps a shop vac in the blow mode hooked to the air inlet under the stove would tell us more...with the stove off, of course!

 

[Skier76]

I'm tempted to toss in the Euro plate and see what happens. My only concern would be the blackening of the glass like mentioned.