Friday, October 3, 2008

Friendly reminder

Don't be fooled - compare before you buy.
As a consumer myself, I don't like being ripped off nor do I like a vendor giving me a lot of hype about their product. I write this article because this is exactly what I see happening to you when your shopping for a replacement catalytic combustor for your woodburning stove. Trust me, I know because I have sold catalytic combustors for 18 years to stove manufacturers, dealers, and consumers. I also know what they should sell for at a reasonable prices.
I'm not talking about quality of the product, I strictly talking price. All catalytic combustors for wood burning appliances are EPA approved and have basically the same noble metal coatings. Therefore, I am not promoting any manufactures product. I just want you to beware of the so called "sale price" and other hype you see when trying to buy a replacement catalytic combustor for your wood burning appliance.
Here are a few examples that I recently ran across on-line:
1. I noticed on e-Bay a seller offering combustors for a so called "special price". They say, the retail price is $163.79 and are telling the consumers they will save $45.69. I take this to mean the consumer pays $118.10. However, the manufacturer sells the same product and combustor size for $109.51. I ask, is this a marketing tactic, hype or rip off?
2. I found a dealer advertising a big combustor sale. "Prices slashed". So what's wrong with that? As I studied this "big sale", I noticed they advertised only by stove model and not by combustor size. Since many combustors are the same size and interchangeable with other stoves and models, I feel the combustors should be sold for the same price. These combustors are sold to dealers by part number and sizes, not by the stove they are used in. In other words the same size combustor should be sold for the same price. Sale or no sale.
What this store was doing, was putting special prices on their home page to lure you in, but offering deals only on combustors for stove models that don't sell and probably never will. In fact, the stove companies have been out of business for over 20 years. The catch is, combustors of the same size and used in other stoves still made today, were priced at their regular price.
Don't be fooled, shop and compare before you buy.
If you have a story to tell or need advise on buying a catalytic combustor for you stove, please let me know.


Matthew Nicoll said...

I am considering getting catalytic combustors for my RSF HF65R wood furnace. What do you know about the metallic catalyst advertised at

Unsurprisingly, they say their metallic ones are better than ceramic ones!

Are you familiar with the RSF furnaces? I know they were advanced in their day - how do they compare efficiency-wise with more modern large wood stoves?

Tim Cork said...

Mr. Nicoll,
Sorry for the delay in getting back to you.
However, I do have answers for you.
Let's start with the metal monolith catalyst.
In certain applications metal monolith has an advantage. It has a lower potential light off temperature because it has less mass and thus heats up faster than ceramic. Most positives have a corresponding negative and metal is no different. It also cools off faster and creates the problem of inadequate temperature and condensation of compounds that can mask the catalyst sites.

Metal Monolith is more sensitive to overtemp. It’s temperature stability is poor. Metal foil manufacturers generally have max temperature limits of 900°C (1652°F). Embrittlement happens more easily on metal vs. ceramic. Sulfur, Phosphorous, Potassium, and Sodium are natural in trees and react with metal foil.

The thermal expansion of the ceramic and its gamma alumina washcoat are tuned to each other. Metal has a much higher thermal expansion and reacts to temperature changes more quickly. The issue thus created is metal monolith can lose its coating through peeling or spalling while the ceramic porosity and lower thermal expansion create both a mechanical and chemical bond.

I don't believe there are any woodburning stove manufacturers in the USA using the metal monolith today.
I worked with a company in Vermont back in the early 1990's that tried these units and they did not work for them.
A few years ago another catalyst manufacturer introduce them again to the industry, but had no luck.
Even some of our distributors and dealer for Applied Ceramics took on the metal catalyst, but had no luck selling them either. That's why you see them on EBay. They sell them to consumers that don't any better. I could go on and on, but I think you get my point.

As for RSF, they sold out to Industrial Chimney Inc. in 1997. I have worked with their people for many years and sold them a lot of ceramic catalyst during that time.
To compare efficiency with other woodburning appliances. Go to the main page of my blog and scroll dow the right hand side. At the very bottom you click on the EPA site that will give you the efficiency of all certified woodburning appliances.
Hope I have answered your questions. Sincerely, Tim