Marks showed up on surface of Princess Ultra?

[BlazeBoy]

Hey everyone,

Had our blaze king installed in November of '24, been running almost constantly since then, has been great and we love it no problems with our 25 foot chimney.

However, this morning I woke up to put a little more wood in and noticed these random marks on the surface of my stove... I have no idea what these are and they were not here last night. 2 adults and I'm the only person operating this stove so no kids throwing random crap on it, and nothing leaking from above.

A little annoyed with how it looks now and we're careful never to put anything on it! But more importantly I'm worried that it's some kind of manufacturing defect? If it's cosmetic it's fine I'll get over it, but I'm worried it's something inside? Maybe an interior weld or something that's showing signs of something?

I don't know... It's seems like plastic but it doesn't come off, it's almost like the steel bubbling up but it's very smooth.

Anyone seen this? Or any idea how to figure out what it is? Stove seems to be functioning fine I have it on right now too, but if this is a sign of something coming I want to get ahead of it. Thanks!

 

[BlazeBoy]

Okay scratch all this.. We just got it real hot and was able to somewhat clean it off, I think the paint bubbled?

 

[stoveliker]

This is right where the cat is, so that got very hot indeed. A new cat getting very hot is common. I've not seen paint complaints from that though.

 

[BlazeBoy]

This is right where the cat is, so that got very hot indeed. A new cat getting very hot is common. I've not seen paint complaints from that though.

Just strange I been using it for 3 months and have gotten it super hot before... and over night when it was on low it had this paint bubbling? Maybe a bug or something landed on it lol, I'll keep an eye on it, winter is far from over

 

[stoveliker]

Yes, that is a bit unexpected.
Although the thermostat being on low can result in a hotter cat!

 

[BlazeBoy]

Yes, that is a bit unexpected.
Although the thermostat being on low can result in a hotter cat!

Interesting, what's the reasoning behind that? We did yesterday buy some curtains that block a doorway which resulted in much better temperature in the living space... And this paint thing happened the very same day. I'm wondering now if it's related

 

[stoveliker]

I can't speculate how the curtains would influence this.

But regarding the stove, choking down the air with the thermostat will decrease the combustion with primary flame (it'll just glow if choked down enough). However, this results in much more smoke and half-combusted gases - this is "dirty choked fire". The cat combusts those gases to (ideally) complete combustion.

As a result, decreasing the air to the firebox will decrease the primary combustion, but increases the fuel (gases) that the cat combusts.
That secondary catalyzed combustion is also exothermic, i.e. it creates heat. More fuel (gases) for the cat to eat results in more heat produced in the cat.

The overall output of the stove will go down when you decrease the thermostat/primary air. But not only does it go down, the heat production also partially shifts from the firebox to the cat.

 

[BlazeBoy]

Understood, what you're saying makes alot of sense. The thermostat on the BK can control the primary combustion but there there's no way for it to control cat combustion... Now the real question is, is this damaging to the catalyst? Especially if it got hot enough to bubble the paint that seems crazy... Will have to do some experimentation..

 

[stoveliker]

Indeed. You don't want to be able to both control primary combustion (==secondary fuel production!) AND secondary combustion, because there's only one sweet spot where the gaseous fuel production in the primary fire is equal to the secondary combustion fuel consumption, and the cat will reach that point (slowly, so intermittent smoke may happen) by just doing its thing.

New cats (before a cord or so is burned) do have the tendency to be overactive, the cat gauge can get beyond the active range.
But they'll settle down into adult behavior on their own. Nothing we can do about their rowdy teenage years or their settling down. It's fine.

But, I have not see paint bubble complaints like this yet, so their relation makes some sense to me but is speculation.