Progress Hybrid cat question / smoke smell

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My cat accumulates ash fairly rapidly. I've wondered if it is my wood (Red Maple, CSS about 20 months with first year outdoors), or if it is a strong draft (tall chimney with insulated liner, house out in the open). Just cleaned the cat during a "warm" day recently, and wife noted that it had only been 2.5 weeks since the last cleaning. It wasn't as bad as I've let it get before, but you could see a clear difference in the flames as the bypass was closed. It probably doesn't help that my screen isn't retaining its shape very well (add heat and it soon sags). We are burning 24/7 (burned 4 full cord to date this season), 18" medium-sized splits.

Regarding smell, we occasionally (rarely) have a slight smell. All gaskets are original. I suspect a clogged cat would accentuate to any smoke leaks.

We aim for higher stovetop temps (500-600), and as a result see a little higher flue temps than you are seeing. Almost always a secondaries burn going in this colder weather.
My screen sags in the back also, heat sags faster now than before and I have noticed cat fly ash worse with the screen sagging, not alot but worse than with the screen fitting tight. (same wood all along)
I called Woodstock with my findings and talked with the guys in the back about brainstorm I came up with to mount a small strip of stainless with screws so the screen could rest on it in the back an not gap sag with heat.
They said they would do some experimenting this week cause the holes were already there in the secondary plate to mount it to (a couple of the air holes) they said there were plenty of them so using 2-3 of them shouldn't affect anything. said they would get back to me later this week or next an that it might work.
They sure are some great people to work with, for any of the small issues I've had.
I received my new cat last friday ( warped problem ) the new one has 3 strap support legs. Looks like it should solve the problem. I dont hear the louder cat heatup pings like the single leg ones.

No smoke smell at all here either, but my draft is a++ so dont get much chance to to leak smoke smell

I burn mostly locust-oak and I do half to close the air down at a slower pace on load ups to get the load charred good for proper lower burns, compared to softer woods.

Todd2
 
I just checked my screen. It had quite a bit of white/gray ash build up - I'd guess up to 1/3 compromised.

I had it out less than a month ago, bent it, cleaned it well, reinstalled. Had an awful time getting it back in. Don't want to take it out to clean it. Just tried scraping it with the poker, which did some good. How is anyone cleaning it, who is cleaning it insitu in a hot stove?

When I took the screen out and bent it (because of sagging), I bent it a LOT, and had a really hard time getting it back in. And it still sags down. Not as bad a before, but still. I bent it so much the screen has real dimples where the cotter pins are. No point in trying to bend it more. I find if I wack the screen forward pretty nicely with the poker it snugs up...for a short time.

Machria, I was going to tell you that you do indeed need a new cat, but Woodstock beat me to it. I had to replace mine recently. My new one has been in use just under two weeks. I'm wondering what it looks like, having seen the build up on the screen. I don't really want to take the cat out more often than I have to, because i don't want issues with the gasket. I also really don't want to get the stove cold when it is 5 degrees out....

I have definitely had my cat get plugged and had to clean it. This never happened with the fireview, but we had bigger honeycombs in the Fireview. This cat, I'm sure, is more efficient at burning the smoke/gasses. Wonder if any Fireview owners who have switched to stainless cats are finding they are either burning less wood or producing more heat from the same wood? Also, if their cats are getting plugged? They have a much less fine screen, so you'd think they'd have a bigger problem.

Tim, go ahead and call Woodstock. They'll send you a new cat. It is likely an issue with the cat. When you get the new one, I'd clean the old one in vinegar and water, and keep it as an emergency back up. When my 1st replacement cat warped, I used the old one which I had cleaned and kept, and it did the trick while I waited for the 2nd replacement.

Which brings me to a question...Where do you clean your cat, if you have cleaned it? The recipe calls for soaking it in a bath of 1/2 vinegar. 1/2 soft water. I don't have anything except my bathtub long enough to hold this cat, and don't intend putting that much vinegar in a tub....did a halfway decent job, on an angle in my sink (yuk), but would love any suggestions for something long enough and small enough in volume to make sense for this stove's cat....

Though, I do seem to have a stronger draft with this stove than I had with the Fireview, and that may be the source of many of my problems. I'm sure this is at least in part because I moved from rear exit flue with 90 degree bend up, to verticle exit flue. May also be in part stove design. I do have tall internal stack and excellent draft. Wondering if others with clogging issues of screen/cat have a similar set up. The currents may be strong enough to be pulling ash up. I'm certainly getting hotter flue temps than I want, and in cold weather cannot get rid of flames in the box.

Last year, when I first had the stove, because of this issue, Woodstock told me to just close the cat right away upon reloading, and let the cat engage whenever it was ready. I did that, and found I could get a really long cat burn. However, I stopped doing it this year because of all the negative reactions of people on the forum to the process of engaging the cat before the stove temps were up. So, before putting in a damper, which I am afraid is going to require all new double wall chimney pipe, I'm going to go back to trying the cold engagement of the cat.

I'm have no idea why my cat is getting plugged. Burning the same types of wood I have for years.
 
rideau said:
Last year, when I first had the stove, because of this issue, Woodstock told me to just close the cat right away upon reloading, and let the cat engage whenever it was ready. I did that, and found I could get a really long cat burn. However, I stopped doing it this year because of all the negative reactions of people on the forum to the process of engaging the cat before the stove temps were up. So, before putting in a damper, which I am afraid is going to require all new double wall chimney pipe, I'm going to go back to trying the cold engagement of the cat.

I often wonder why people are so infused with making sure the stove is up to temp before closing bypass. It really will have no affect other than slowing the fire down via less draft. As long as your not doing this with "cold air" in the stove which could damage the cat from the large temp differential, I don't see why it is a problem at all. That said, I always wait for 260 to 300 pipe temp before turning it.


What gasket are you worried about damaging when removing the cat? The gasket is in the back of it, and doesn't move when I remove the cat. ? ?
 
Mine came lose on one section in the bottom, and a number of other people have had theirs come lose at the top and have had to reglue the gasket. Woodstock gave me gasket glue for it, rather than cement. I just don't want it to come lose.

That being said, when I checked my screen a about an hour ago it was rather clogged, so I decided to go ahead and check the cat...even though it is new and has only been installed for 10 days.

Glad I did!

Surface was completely covered with fine white ash. Completely. So I brushed it off and reinstalled it.

I'm really beginning to wonder if my draft is ridiculous? Can't imagine why there is so much ash getting pulled up.

I have loaded the stove with a 3 inch round of ash, a 4 inch round of ironwood and a decent size split (about 7" on all sides) of maple, as well as a few small ironwood branches. And I have closed the air completely and the bypass in closed. Did this 14 minutes ago. On a decent bed of colas, but not a large one, because I had burned down pretty much before checking the cat. So I'll see how long it takes for the cat to light off. Maybe if I burn this way the stove will stay in cat mode and the cat will stya clean. We'll see if I get enough heat with the cold temps out...5 degrees F tonight. And a bit windy.
 
My screen looks to be about 1/2 plugged and it was brushed off the last time I removed ash from the firebox - I may have even removed it for cleaning, or maybe it was the time before that. Anyway this was sooner than I would usually clean it as the firebox ash build up is not excessive yet. I wonder why so much fly ash?

I didn't get to the cat yet because there were too many hot coals to get burned down. I'll find out tonight but I'm sure it's partially blocked by fly ash.




Mine came lose on one section in the bottom, and a number of other people have had theirs come lose at the top and have had to reglue the gasket. Woodstock gave me gasket glue for it, rather than cement. I just don't want it to come lose.

That being said, when I checked my screen a about an hour ago it was rather clogged, so I decided to go ahead and check the cat...even though it is new and has only been installed for 10 days.

Glad I did!

Surface was completely covered with fine white ash. Completely. So I brushed it off and reinstalled it.

I'm really beginning to wonder if my draft is ridiculous? Can't imagine why there is so much ash getting pulled up.

I have loaded the stove with a 3 inch round of ash, a 4 inch round of ironwood and a decent size split (about 7" on all sides) of maple, as well as a few small ironwood branches. And I have closed the air completely and the bypass in closed. Did this 14 minutes ago. On a decent bed of colas, but not a large one, because I had burned down pretty much before checking the cat. So I'll see how long it takes for the cat to light off. Maybe if I burn this way the stove will stay in cat mode and the cat will stya clean. We'll see if I get enough heat with the cold temps out...5 degrees F tonight. And a bit windy.
 
My plan for cleaning the screen in place was a grill brush, but like I said I haven't had to do it. It should be very simple.

I haven't seen any change in cat accumulations with my sagging screen. IDK why others are having issues with accumulation. The screws into air holes idea could be a good fix. My original screen gunked up very fast and was a real PITA to deal with. The new screen doesn't gunk up at all and I haven't noticed any change with the cat. It didn't even gunk up when it still fit tight. When I took it out to bend it back in place it only had a little bit of flyash on the ends.

As for cleaning the cat, I'm just refering to cleaning the flyash off. The vinegar soak shouldn't be necessary except very rarely.
 
My plan for cleaning the screen in place was a grill brush, but like I said I haven't had to do it. It should be very simple.

I haven't seen any change in cat accumulations with my sagging screen. IDK why others are having issues with accumulation. The screws into air holes idea could be a good fix. My original screen gunked up very fast and was a real PITA to deal with. The new screen doesn't gunk up at all and I haven't noticed any change with the cat. It didn't even gunk up when it still fit tight. When I took it out to bend it back in place it only had a little bit of flyash on the ends.

As for cleaning the cat, I'm just refering to cleaning the flyash off. The vinegar soak shouldn't be necessary except very rarely.

Yes, Waulie, I know that. When I took my original cat out, I wanted to clean it because I wondered if it wasn't working well because of accumulation inside the cat. Also, for a back up if anything happened to the new cat. (Glad I did clean it!) At that time, I could not find anything big enough to soak the cat, because of its length. SO I just want to get any suggestions for siomnething reasonable.

Thanks.

By the way, I am into my second fire that I am starting the way Woodstock told me to last year...loading up on coals, shutting everything down immeditely, and just ignoring the stove from there on. Find it takes about 25 minutes to get to active flames, and I do get active flames throughout the burn until down to coals, just like I do with a regular start, BUT there is a big difference. On the first fire the flue temp never went above 500. I strated my second fire about 25 minutes ago, it has just broken into lots of flames, so I'll watch and see what the flue temps do this time.

Thanks for the suggestion of a grill brush. I'll get one.
 
By the way, I am into my second fire that I am starting the way Woodstock told me to last year...loading up on coals, shutting everything down immeditely, and just ignoring the stove from there on. Find it takes about 25 minutes to get to active flames, and I do get active flames throughout the burn until down to coals, just like I do with a regular start, BUT there is a big difference. On the first fire the flue temp never went above 500. I strated my second fire about 25 minutes ago, it has just broken into lots of flames, so I'll watch and see what the flue temps do this time.

Thanks for the suggestion of a grill brush. I'll get one.

I'm really curious if you do this and check the chimney is it smoking at all?
 
I'm really curious if you do this and check the chimney is it smoking at all?

I just went out to check..in sweatshirt and a light pair of garden gloves since I was just going to take a quick look at the chimney. Artan (Wheaten) slipped out with me and thought we were going for a walk, so we did...down the road, where I picked up a couple of 3 inch branches I had pulled to the side of the road, and carted them home. OMG! It's cold out there. My fingers are freezing.

My flue temp is 540, my stovetop on the cast next to the verticle exit is 330, and I DO have some smoke coming out of the chimney. Good fire going in the box too, now 45 minutes into the burn, which doesn't happen with a regular start up. The fire is relaly active now, glass clean, etc. Am going to pop outside (without Artan!) and see what the chimney is doing.

I'm a softie. We went for another walk...upsides, I had on polartec lined wool mittens and got a few more branches into the yard before our expected snowfall...Downside, there is still smoke coming out the chimney...but: maybe it is steam? It is 14 out, wind out of the north (feels colder!), and the stuff coming out of the chimney is completely gone before it reaches the front of the roof...I'd guess gone in about ten feet. If I stand under the eve I can't tell it is "smoking". Stovetop temp is 390, flue is 580, glass is clear, constant but slow wispy flames arising from coal bed area...coals bright red, bottom of lowest split red, no activity at the secondary air holes....a good burn, but not a cool flue. I think it is steam I am seeing. Will see if it is gone in a few minutes, when most moisture should be out of the wood.

Have noticed steam a few times in the past during the early part of the burn, when conditions are just right (or wrong) outside. Today cold (14), wind out of the north, and quite humid air...we are about to get a snowstorm.
 
Machria;

Was the "slight bend" on the left side of the frame, kind of like it was not completely bolted down properly? Any chance you could post a picture?

Here ya go....
 

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The newest cat in the PH Rock, 7 days of light 24-7 burning so far so good.
cat.jpg
cat.jpg
 
Interesting - if you look at the two cats posted above (Todd2 and Machria) you can see that they had a change in design... Note the additional supports (3 on the newer one vs 1 on the older).
 
Interesting - if you look at the two cats posted above (Todd2 and Machria) you can see that they had a change in design... Note the additional supports (3 on the newer one vs 1 on the older).
My first 2 warped like Machria's. They put me on the list for this improved version and I received it last wed.
I asked them if cat burning at 500 to 550 center stone temp and rear cast top beside top flue pipe (thermometer & IR gun measured alot while learning the stove) was hard on the cat, they said by no means that it is just a bug they were working on with the cat Mfg. Seems to be doing the trick but I haven't went much over 450 top temp. the past 7 days.

Todd2
 
Todd, looks like you also have a visible gasket around the front edges of the cat? I only have a gasket around the back of the cat (have to reach I with it removed to feel it). Am I missing that gasket? Anyone else have that ?
 
Todd, looks like you also have a visible gasket around the front edges of the cat? I only have a gasket around the back of the cat (have to reach I with it removed to feel it). Am I missing that gasket? Anyone else have that ?
It is a small sorta soft rope gasket that you shove in with a putty knife with the cat already in place. Woodstock said its to hold it in place to the seated gasket.
 
The cat screen was about 50% plugged, photo snapped after some was aready removed.
I found this build up to be harder to remove and required a brass brush from both sides to get it cleaned- also this was brushed off from inside the firebox ~ 2 weeks ago:
pluggedscreen_zps23519aca.jpg



So I'm really wondering why so much build up in a short time.. at this rate I'll need to clean both screen and cat everytime the firebox ash build up needs to be removed.

Here is the entry side of the cat about 3-4weeks since the last cleaning- I'd say about 85% plugged. The fly ash was easily removed with the shop vacuum.

pluggedcat_zpsc099a3c2.jpg
 
The cat screen was about 50% plugged, photo snapped after some was aready removed.
I found this build up to be harder to remove and required a brass brush from both sides to get it cleaned- also this was brushed off from inside the firebox ~ 2 weeks ago:

So I'm really wondering why so much build up in a short time.. at this rate I'll need to clean both screen and cat everytime the firebox ash build up needs to be removed.

Here is the entry side of the cat about 3-4weeks since the last cleaning- I'd say about 85% plugged. The fly ash was easily removed with the shop vacuum.

I hate to suggest it but how is your wood supply? Last fall I had a few sizzlers in my wood and both the screen and the cat had far more buildup than I do now and I haven't seen a sizzler since last November.

Since all smoke goes through the screen even in bypass mode I wonder if it may just collect more from startups when there is heavier smoke going through there.

Also - do you regularly have that screen heated up to glowing? I've watched the fly ash burn up when it hits the glowing screen.
 
As far as the roll pins in the upper rear corners of the stove (mentioned by Doug60 in another thread) they can be accessed by removing the top stones and cooktop, locate visually with a small inspection mirror and flashlight then I was able to get my fingers back there with a dab of stove cement and work it into and around the pin... I don't know how much smoke smell could actually get through those but we'll see if it makes a difference.
 
I hate to suggest it but how is your wood supply? Last fall I had a few sizzlers in my wood and both the screen and the cat had far more buildup than I do now and I haven't seen a sizzler since last November.

Since all smoke goes through the screen even in bypass mode I wonder if it may just collect more from startups when there is heavier smoke going through there.

Also - do you regularly have that screen heated up to glowing? I've watched the fly ash burn up when it hits the glowing screen.


Wood is a combination of white and red oak tops, and a honey locust I must have cut and split ~ 4 years ago.
It was split and stacked right when I got it, stacked outside until middle of last summer when it was moved under roof in the wood shed- I don't think dryness is the issue, however the oak tops have a higher % of bark and sap wood than wood from the main trunk. I have not noticed any sizzlers this year.

The areas of the screen that were clear are typically the area that is glowing..
 
The cat screen was about 50% plugged, photo snapped after some was aready removed.
I found this build up to be harder to remove and required a brass brush from both sides to get it cleaned- also this was brushed off from inside the firebox ~ 2 weeks ago:
pluggedscreen_zps23519aca.jpg



So I'm really wondering why so much build up in a short time.. at this rate I'll need to clean both screen and cat everytime the firebox ash build up needs to be removed.

Here is the entry side of the cat about 3-4weeks since the last cleaning- I'd say about 85% plugged. The fly ash was easily removed with the shop vacuum.

pluggedcat_zpsc099a3c2.jpg
Holy crap! Somethings not right for sure but I can't imagine what. Does Woodstock have any thoughts on this?
 
Try a 50/50 white vinegar/water soak to remove the hard deposits on the screen. There is a similar but multi-step procedure for a major cat cleaning.
 
Holy crap! Somethings not right for sure but I can't imagine what. Does Woodstock have any thoughts on this?

I'll seconds that! WOW. My screen after 7 weeks of almost 24x7 burning the entire time looks pretty much the same as the day I got the stove.

3fordasho,
Have you checked you draft? Is your draft ok? Me thinks you have something else going on. What kind of lenght chimney do you have,,,,,?
 
I'll seconds that! WOW. My screen after 7 weeks of almost 24x7 burning the entire time looks pretty much the same as the day I got the stove.

3fordasho,
Have you checked you draft? Is your draft ok? Me thinks you have something else going on. What kind of lenght chimney do you have,,,,,?


Draft seems to be ok- flue set up is straight out the back through wall and then straight up 18 or 21'. All but last 4' or so are inside a insulated chase. Pipe is Supervent 6" insulated class A, the short section of connector pipe is double wall.

This is the 3rd cat cleaning this season, the first cleaning it looked like in the picture, but part of that might have been from last season, the 2nd time it was not too bad but I vacuumed it off anyway, and now plugged again.

Woodstock so far is saying the screen should catch the ash and asked it there are open gaps the screen is not covering... I just mentioned there is usually a 1/4" gap along one end because the heat makes it sag. I do bend it back when Ihave it out for cleaning.
 
The cat screen was about 50% plugged, photo snapped after some was aready removed.
I found this build up to be harder to remove and required a brass brush from both sides to get it cleaned- also this was brushed off from inside the firebox ~ 2 weeks ago:
pluggedscreen_zps23519aca.jpg



So I'm really wondering why so much build up in a short time.. at this rate I'll need to clean both screen and cat everytime the firebox ash build up needs to be removed.

Here is the entry side of the cat about 3-4weeks since the last cleaning- I'd say about 85% plugged. The fly ash was easily removed with the shop vacuum.

pluggedcat_zpsc099a3c2.jpg

Could be a picture of mine last night.

Would like to know what this is all about.

Burning same wood I always have, never had a problem with the fireview...but my chimney has lost the 90 degree coming out the rear flue exit of the Fireview when I switched to the PH, and I'm thinking it may be an excess draft issue pulling fly ash up. I gewt flames even witht eh air completely closed in this cold windy weather.
 
Could be a picture of mine last night.

Would like to know what this is all about.

Burning same wood I always have, never had a problem with the fireview...but my chimney has lost the 90 degree coming out the rear flue exit of the Fireview when I switched to the PH, and I'm thinking it may be an excess draft issue pulling fly ash up. I gewt flames even witht eh air completely closed in this cold windy weather.

I suspect type of wood maybe a factor, but I am also burning the same wood in a fireview and have not had the issue there. The fireview has the old coarse screen or flame guard with open sides and still less of a build up issue. It will build up eventually, but this season I've only had the fireview cat out once and it didn't need to be cleaned.