Hearthlist Digest #188 - Wednesday, August 12, 1998 Re: Vent Free by "by way of [email protected] (Craig Issod)" <[email protected] vent free experience.... by "Keith Slattery" <[email protected]> gas fired logs sets for patios by "B & J Hennessey" <[email protected]> Outdoor Gas Logs by "David Issod" <[email protected]>
(back) Subject: Re: Vent Free From: [email protected] (by way of [email protected] (Craig Issod)) Date: Wed, 12 Aug 1998 09:29:04 -0400 (EDT) Many vent free units do emit an odor. However, the odor varies depending on many issues. It is true that CO does not have an odor and that the mercaptans (this is the correct spelling ) are added so that people could smell leaks, however the smell from vent free units is from other sources : 1- The binder used in making ceramic logs. Manufacturers vary the amount of organic binder used in their logs. One source of the smell is emitted from the organic binder burning. 2- Oils that are left on the burners and sheet metal parts from the manufacturing process. 3- Incomplete combustion due to leaks or poor burner design or poor manufacturing process. The leaks could be small and of no significance except to cause formation of compounds like aldehydes that cause the smell because of incomplete combustion. 4- There could be other sources like the paint used on the logs or the metal parts, etc. It is important to note that most of these chemicals that cause odors are at such a low concentration that they would not cause any adverse health effects. It is also important to note that the issue of itchy eyes that some people complain about is mostly caused by other chemicals like NO2. These chemicals are caused by bad design. The ANSI Standard subcommittee is currently addressing how to control NO2 and how to measure it (very complicated issue). The note about a catalytic unit not producing any odor is correct in that the catalyst used in catalytic vent free units tends to oxidize most of the chemicals caused by incomplete combustion and many of the chemicals causing the other odors, they however will not eliminate all odors. Also, some of the designs out in the market place will also drastically reduce NO2. All catalytic units virtually eliminate all the CO produced by the burning process (some units do allow for leaks around the catalyst and thus do not remove the CO completely). I am sure that the above will generate some disagreement and could result in some lively discussion on this forum. I do work for a company that manufactures traditional vent free products as well as catalytic ones. The reason I am somewhat biased about catalytic units is that we were the first company to introduce them. Samir Barudi Superior Fireplace Company
(back) Subject: vent free experience.... From: Keith Slattery <[email protected]> (by way of [email protected] (David Issod)) Date: Wed, 12 Aug 1998 15:16:16 -0400 (EDT) Regarding the first e-mail from Y Aube... Surely the vent free debate will continue for years to come. However, since we sell lots of vent free products, I of course feel the need to respond... First.. a couple of facts. It seems that CO is the major concern from most consumers that are interested in a vent free appliance. While CO should certainly be a concern, it is important that we all educate ourselves about CO and vent free appliances. A well designed vent free appliance in reality should produce very low levels of CO. Many people are not aware of the ambient levels of CO present in their homes without a vent free appliance. Our experience (and keep in mind we are not engineers) has been that properly designed vent free appliances will produce 3-7 ppm of CO when measured at the unit. CO levels of 7 ppm are the average for units operated steady state for an 8 hour period. The AGA vent free standard calls for less than 12 ppm. Other studies have shown that CO in ambient air without a vent free appliance can fall in the following ranges - Rural Areas - Outdoor - 3-5 ppm Indoor - 3-8 ppm Urban Areas - Outdoor - 3-27 ppm Indoor - 3-18 ppm With a vent free appliance the following ranges have been recorded - CO in Ambient Air w/vent free unit in operation - Intermittent Use - Rural - 6 ppm Urban - 6 ppm Continuous 8 Hour Use - Rural - 14 ppm Urban - 25 ppm For comparison, the CO produced from one cigarette is 2 ppm. If you then reference the NFPA's Consumer publication for Carbon Monoxide Risks at Home you will find the following - Concentration (ppm) Symptoms 35 No adverse effects within 8 hours 200 Mild headache after 2-3 hours of exposure 400 Headache and nausea after 1-2 hours * source - US Consumer Product Safety Commission So... I guess my point is that CO tends not to be the major concern for vent free appliances. Of course, log placement and design can effect CO levels dramatically. We would hope that manufacturers of these products would go beyond the requirements set forth by AGA. So... on to the "decorative appliance" issue. The truth is that vent free appliances are technically considered "heaters". While the codes clearly state that these appliances should not be installed as primary heating equipment, we do know that many consumers use these as a dominant heat source. My questions are as follows - 1) What are the experiences of retailers that have sold thousands of these types of products? 2) Are some of the nightmare stories related more to individual manufacturer design or to overall concept design? 3) What are the ratios of problems in regards to LP vs Natural Gas 4) The major concern for most educated manufacturers and retailers relate to humidity levels / proper sizing. What are the field experiences in regards to H20? And... how do these problems relate to appropriate sizing guidelines? 5) The biggest problems seem to relate to two issues - a) Odors - how have retailers handled this? b) Sooting - Is this again product or design related? My last comment on this comes from our experience with retailers and distributors - I have found that you can have two retailers in the same town with dramatically different views on vent free - One retailer (who of course promotes vent free product) will experience very few problems with vent free products. In fact, vent free products seem to be the most trouble free product mechanically speaking. They admit that they take back a few units per year (usually related to odors), but most claim that these products are bulletproof. The second retailer (who of course does not promote vent free products) will talk about endless horror stories of sooting, odors, etc. It usually ends up that the first retailer has sold thousands of vent free products and the second retailer has sold a handful. So... in closing of this endless e-mail, what are the real world experiences.... ? This product category is the fastest growing segment of the hearth industry. Proper knowledge and representation of these products is our responsibility... Keith Slattery Delta Marketing
(back) Subject: gas fired logs sets for patios From: B & J Hennessey <[email protected]> (by way of [email protected] (David Issod)) Date: Wed, 12 Aug 1998 17:58:25 -0400 (EDT) Does anyone have any information on who makes the "campfire" gas log sets that can be installed outside on a patio? I saw them on display at the HPA show in Reno but just can't recall who it was that manufactured them. Thanks, Liam Hennessey Upper Valley Pellet Stoves [email protected]
(back) Subject: Outdoor Gas Logs From: [email protected] (David Issod) Date: Wed, 12 Aug 1998 17:58:27 -0400 (EDT) Heat N Go (http://heatnglo.com) makes an outdoor fireplace of this type. I think there is also another maker on the HearthNet products page at http://hearth.com/prod.html Craig Issod, Webmaster HearthNet at http://hearth.com Everything your Hearth Desires