Appliance adapter color

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BigJ273

Minister of Fire
Feb 15, 2015
712
Maryland
Turned a straw color last year. Today i noticed a spot towards the front that was purple on the exposed part. Normal?
 
Turned a straw color last year. Today i noticed a spot towards the front that was purple on the exposed part. Normal?
Post a pic.
 
And this appliance adapter was previously black? I haven't had one change color quite like that. How have your flue temps been?
 
And this appliance adapter was previously black? I haven't had one change color quite like that. How have your flue temps been?
I’m guessing it’s a stainless adapter.
 
Stainless single wall flue parts often turn brown. A little hotter and they blue. This is often seen on motorcycle exhaust pipes.

Your whole liner is probably brown.

I bet somebody can find the chart for colors of stainless as it heats up.
 
Stainless single wall flue parts often turn brown. A little hotter and they blue. This is often seen on motorcycle exhaust pipes.

Your whole liner is probably brown.

I bet somebody can find the chart for colors of stainless as it heats up.
Yea. The exposed parts of the liner I can see are copper colored. Most of it is insulated except for about the first foot or so from the appliance connector. It also has some purple/blue in this area as well. I’ve asked on here before and been told that’s normal. I’ve just never had purple on the appliance connector until I noticed it today. Not a very big spot, but it’s def new.

I’ve posted a pic of the adapter, and circled the area that has now turned a purple/blue color. I’m not home right now to take a pic of the color change. Before u ask, yes, the adaptor is seated all the way down inside.

06D2555E-28CE-4043-8EA2-8F9868B0BB72.jpeg
 
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Here’s a shot of it.
 

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I’m not a pro so I’d take my input with a grain of salt. That area looks it got hotter than it should have. Maybe stove was accidentally overfired or some buildup ignited in that area? What does the liner itself look like right above the adaptor? The pros on here should be able to give you solid input on this.
 
No recollection of where there could have been an overfire. The liner above it is straw color with some purple tinge. The part that’s not wrapped In insulation. My guess is the adapter and liner are exposed to oxygen where they are located, which prob contributed to the color. Idk. I poked around on it last night. It seemed solid. I’m gonna take a look from the inside in the morning
 
Lots of times during warm up you’ll have the throttle open enough to actually get flames up into the chimney. Especially if you have a bypass. Hot enough to blue stainless.
 
That kind of coloration shouldnt be taken as an indication that the liner is compromised in any way but it does mean that the surface got pretty hot at one point. Pretty typical for a stove especially if you are burning it hard.

It's a little more complicated than just temperature. The specific color depends on the thickness of the oxide layer that has formed on the steel so the duration and surface finish also affect it. But generally if the color suddenly appeared then you can get a pretty good idea of the max surface temp from the chart.
 
The other thing I was looking at while taking this photo-this adaptor is as far in the stove as it can go, all the way seated. But u can see it’s not flush with the stove, like it was with my older insert. Is that a safety concern? There are no gaps.
 
The other thing I was looking at while taking this photo-this adaptor is as far in the stove as it can go, all the way seated. But u can see it’s not flush with the stove, like it was with my older insert. Is that a safety concern? There are no gaps.

It’s a tapered adapter and all stoves use different diameters which is crazy but true so the tapered adapter will go in different distances/depths depending on what diameter the appliance flue collar is. You really don’t want it to bottom out at the bottom, you want the taper to get tight first. That’s the seal.
 
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Liner being straw colored with some purple tinge describes my liner before the insulation starts as well, for what it’s worth.
 
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Your label didnt get hot enough to burn off so I think your good to go.
 
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