JV_Thimble said:
Of the top of my head I recall that stainless is not a ferrous metal, specifically, it lacks sufficient iron content for magnetic attraction. I can't remember the various components of stainless of the top of my head.
VC Encore Cat - Behind the Fireback
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Of the top of my head I recall that stainless is not a ferrous metal, specifically, it lacks sufficient iron content for magnetic attraction. I can't remember the various components of stainless of the top of my head.
I wonder who VC buys their steel cats from. I have a Condar Steelcat in mine, and one time I accidentially let it get away from me and saw 2000F on the probe thermometer (shut it down FAST!).
Even with that abuse mine isn't warped.
Even with that abuse mine isn't warped.
Some stainless steels are magnetic. And some can rust too.
Chrome and nickel are the 2 main ingredients that make a steel stainless. The more you add the more corrosion resilient but the softer the metal. Its the nickel that causes the non magnetic property. When you buy stainless knives for instance you will see a number like 18/8 or such - that is chrome % / nickel %. The magnetic stainless blends have to contain zero nickel I believe.
This is also why you sometimes get rust spots on "stainless" knives. The very highly resitant stainless blends have a lot of chrome and end up too soft to hold a sharp edge, so knife makers will typically use a high stainless mix for the handle and a low stainless, high carbon mix for the blade.
Chrome and nickel are the 2 main ingredients that make a steel stainless. The more you add the more corrosion resilient but the softer the metal. Its the nickel that causes the non magnetic property. When you buy stainless knives for instance you will see a number like 18/8 or such - that is chrome % / nickel %. The magnetic stainless blends have to contain zero nickel I believe.
This is also why you sometimes get rust spots on "stainless" knives. The very highly resitant stainless blends have a lot of chrome and end up too soft to hold a sharp edge, so knife makers will typically use a high stainless mix for the handle and a low stainless, high carbon mix for the blade.
Our 2550 new 3 years ago came with ceramic cat. About a year ago the dealer said VC had shipped 2550 cat models with steel combustors but they quickly went back to ceramic cats because of many troubles the steel combustors had. Please keep us posted on their response and solution.
Gark said:
Will do - was having some major DSL/ISP problems the past couple of days. Seems they may have fixed it - we'll see.
FYI, the parts came into the dealer and I've picked them up. Install is scheduled for Thursday. Will keep you posted.
Hey JV,
A while back I posted about the need for a cat probe thermometer on these stoves. I think they are a must for the Encores and any other cat stoves for that matter. My DW came with one and so do all the current DW's. My Encore, which I never got to install and traded because of moving, did not have one as none of them come equipped with cat probes. The DW was almost inoperable without a thermometer on top you had to always have an eye on the cat temp to know when to reload or add cat air in order not to overfire. In your case, it looks like it could have had something to do with an overfire, not your fault! It is almost impossible to detect a cat overfire on these stoves: one cannot see the actual cat or measure its temperature with the recommended griddle thermometer! I would highly recommend a cat probe thermometer for these stoves. In fact I think if VC made it a stock item they would have lots of happier customers and less problems with the refractory and cat crumbling. I would also make sure that the thermostat on the back of the stove is operating properly and letting air into the secondary combustion chaimber the cat sits in. As others stated it may also have had something to do with cat oversize but I doubt it, looks more like warpage due to overheating!
Good luck!
A while back I posted about the need for a cat probe thermometer on these stoves. I think they are a must for the Encores and any other cat stoves for that matter. My DW came with one and so do all the current DW's. My Encore, which I never got to install and traded because of moving, did not have one as none of them come equipped with cat probes. The DW was almost inoperable without a thermometer on top you had to always have an eye on the cat temp to know when to reload or add cat air in order not to overfire. In your case, it looks like it could have had something to do with an overfire, not your fault! It is almost impossible to detect a cat overfire on these stoves: one cannot see the actual cat or measure its temperature with the recommended griddle thermometer! I would highly recommend a cat probe thermometer for these stoves. In fact I think if VC made it a stock item they would have lots of happier customers and less problems with the refractory and cat crumbling. I would also make sure that the thermostat on the back of the stove is operating properly and letting air into the secondary combustion chaimber the cat sits in. As others stated it may also have had something to do with cat oversize but I doubt it, looks more like warpage due to overheating!
Good luck!
VCBurner said:
Much appreciated, VCBurner. Can you point me towards your post on this topic? That should help me figure out exactly what I need to do.
Cheers,
John
JV_Thimble said:
No problem John,
I have posted on various Vc Encore threads, you can always go onto my profile and check out my posts, if that helps. Lots of guys have shared information with me about this stove. You can also type VC Defiant Encore in the search bar at the top of the page and find lots of info. I'll look up some of the threads and post back with an update.
https://www.hearth.com/econtent/index.php/forums/viewthread/68912/
https://www.hearth.com/econtent/index.php/forums/viewthread/72135/
https://www.hearth.com/econtent/index.php/forums/viewthread/66655/P88/#805621 This is where we talk about the probe thermometer. This thread also has links to pics of a probe thermometer. They come with a digital read out. You can get them from a dealer or online, they get inserted into the back of the stove and into the secondary chaimber somehow. The dealer would probably tell you all about it. I think they go for about $80 online if I remember correctly.
Take care,
Chris
Had the stove repaired/parts installed on Thursday, and started the stove on Friday morning. All seemed to work well.
The installer is not a fan of the cat thermometer concept, favoring a probe thermometer in the double-walled flue pipe. Seems to me the most critical reading here (after the basic stovetop temp, just behind the griddle) is the cat temp. This model from Condar looks like a good way to go -
http://www.condar.com/digital_monitor_woodstoves.html. I may order one soon. Don't want to overfire the cat, if that's something I can do without being able to measure the cat temp directly like this.
The installer is not a fan of the cat thermometer concept, favoring a probe thermometer in the double-walled flue pipe. Seems to me the most critical reading here (after the basic stovetop temp, just behind the griddle) is the cat temp. This model from Condar looks like a good way to go -
http://www.condar.com/digital_monitor_woodstoves.html. I may order one soon. Don't want to overfire the cat, if that's something I can do without being able to measure the cat temp directly like this.
JV_Thimble said:
I doubt you'll overfire the cat as I never did over the course of 20+ years.. I used the cat temp as an indication of when to close the bypass and for that it's important.. By design cats do not tend to overheat but when new they are at their hottest and even then they generally do not exceed 1400 degrees..
Ray
JV_Thimble said:
The installer is not a fan of the cat thermometer concept? :exclaim: He must want you to come back for parts when you overfire your cat! :wow:
One of the most critical readings in a cat stove is the cat temperature. Many catalysts burn out too quickly due to constant overfire. I use the word overfire loosely, they may actually be within range of a cat, but constant high temps may damage not only the cat but parts around it. These Encore catalysts and refractory housing are among the most expensive in the market. They also tend to last the least amount of time. I have never overfired the cat on my Dutchwest but had the cast iron parts around it glowing red, the Dutchwests were known for warpage of the top plate due to catalyst having extremely high temperatures. The newer Dutchwests that replaced Consolidated DW, like Ray's, featured a refractory housing in order to insulate parts around the cat from the high heat created by the catalysts. Temperatures like this may cause some unesessary warping and damage to the refractory housing and cat in an Encore, due to expansion of metal parts around it. I agree that the griddle temp is just as important to measure firebox temp, but measuring the temperature inside the flue pipe close to the stove is just like measuring flue temperatures. Although, some feel flue temps are equally as important, including myself, they do not replace catalytic temperature measurements in any way. The Condar thermometer you pointed out specifies that the probe should be inserted 1/2 inch away from the catalyst. It is the same one I had researched for my Defiant Encore and I know of others who have used the same probe with great success. I highly recommend it, you'll know when there's an overfire or when it's time to reload the stove if the cat temp is too low! If the dealer doesn't want to tell you how to install the probe I'm sure you can find out here. There are dealers around here too who would be willing to give you this information. JClarks is one who I know is always willing to help out.
raybonz said:
This sounds like a good plan. Use the cat probe to better operate the stove and better understand what's going on.
VCB - Didn't actually talk to the dealer at all on this. The installer is a sweep that's done a lot of stove repairs. However, I think I'm best off doing this without the dealer anyway. Their guy that owns one of these stoves runs it way too cool, in my opinion. When he was out once, he mentioned getting it up to 250 F in the morning, switching on the cat, closing the supply air most of the way, and leaving for the day. I suspect he never really activates the catalyst. At the same time, when I mentioned needing to get over 450 to activate it, he thought I was pushing things too hot. So, better off on my own with support from Hearth.com.
Thanks JV_ for the report. Questions (just wonderin) - did the repair guy put in a new steel cat or ceramic? Was the refractory box replaced and did he have to remove the upper fireback to replace it?
Gark said:
I believe with this model the upper fireback is removed to replace the cat. Also, I saw no damaged to the assembly (refractory box) so replacing it did not seem needed.
On our 2550 cat, the stovetop temp. is only loosely related to what serious heat is happening in back of the stove. I've seen griddle temp of 550 f. and the back of the stove at 830 f. The top of the refractory box was glowing like an incandescent bulb filament -white hot. You can see it through tiny slits above the hood on either end about 3 in. from the ends of the rods that hang the exhaust hood. Gonna get a probe and install it in the refractory after seeing the pics of your sagging combuster.
Good luck guys, I was looking forward to firing up my Defiant Encore this year, now it'll be just a memory.
Take care.
Chris
Take care.
Chris
Gark said:
They replaced 3 parts - the refractory box, the cat, and the refractory box cover (for lack of a better term). I didn't actually have a close look at the cat while they were doing all this. Still have the box it came in (from Sud-Chemie) and can always remove the fireback to have a look. May do that when I install the cat thermometer.
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