Home Ventilation System Clarksville TN
Monday 8:00 AM - 7:00 PM
Tuesday 8:00 AM - 7:00 PM
Wednesday 8:00 AM - 7:00 PM
Thursday 8:00 AM - 7:00 PM
Friday 8:00 AM - 7:00 PM
Saturday 8:00 AM - 4:00 PM
AC Unit Installation, Central AC Installation, Commercial HVAC Service, Furnace Installation, Heat Installation, Heat Pump Installation, HVAC Cleaning, HVAC Contractors, Residential HVAC Service, Ventilation System Service
Service Types and Repair
AC Unit, Central AC, Furnace, Heat Pump, Heater
Clarksville , TN
Clarksville , TN
services and repair
A/C Repairs, A/C Installations, Indoor Air Quality, Metal Duct Work, Walk-in Coolers, Walk-in Freezers, Duct Cleaning, Gas Furnaces, Electric Heating, Heat Pumps, Heat Recovery Units, Attic Fans Ventilation, Maintenance Agreements
Mon - Fri - 9-5, Sat 10-2
Home Ventilation System
Pity the homeowner who tries to sort out the facts about unvented gas heaters. Unvented fireplaces have become popular over the past two decades because they are designed to be installed anywhere in a home without being vented outside. Homeowners find that flexibility and simplicity hard to pass up. Yet as their popularity has built, so has opposition. Critics say unvented heaters are potentially dangerous - a source of indoor carbon dioxide, carbon monoxide, nitrogen dioxide and damaging moisture. Stories critical of them have appeared in such publications as Consumer Reports and Popular Science, and the Internet is well-stocked with sites alleging that they are health hazards. The criticisms are untrue, say the manufacturers, 26 of which have banded together as the Vent-Free Gas Products Alliance.
(The industry prefers the term "vent-free" over unvented or ventless.) The alliance says the devices emit negligible amounts of byproducts and are equipped with "oxygen detection safety" pilots that shut them off if a room's oxygen level falls below 18 percent - protection against the buildup of potentially lethal levels of carbon monoxide. Further, it notes that a 1996 American Gas Association study concluded that, when properly used, unvented heaters performed "well within nationally recognized guidelines for indoor air quality" as measured by levels of oxygen, carbon monoxide, carbon dioxide and water vapor. And it adds that it knows of no deaths due to emissions from an unvented gas product in the past 20 years.
Those points don't quiet the critics, who point to the phrase "properly used" as the key. They say many homeowners use the devices too much, sometimes as the primary rather than supplementary heat source of the home. It's only prudent, they say, to avoid breathing the byproducts of combustion, however minimal they may be. They note, too, that three states - California, Montana and Massachusetts - don't allow unvented fireplaces in homes. (The industry replies that Massachusetts and California are moving to allow them.) Homeowners seeking guidance might have gotten some from the American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE), a committee of which spent much of last year creating a new standard for home ventilation.
Early drafts of the standard addressed the need for venting gas appliances, but that language was removed when the industry objected. The final version of the standards avoids mentioning unvented heaters altogether. The committee sidestepped the issue, but committee member John Proctor, president of Proctor Engineering Group in San Rafael, Calif., doesn't hide his feelings on the topic. High on Proctor's list of reasons for objecting to unvented heaters is that they generate water vapor, which in a tight house can lead to mold, mildew and rot problems. (The industry defends itself on this point by noting that the unvented devices eliminate the need to run a humidifier.) "My advice to consumers is quite simple: Don't buy one," Proctor said. "I don't think any engineer who stops and thinks about it and isn't paid by the gas industry would say it's a good idea."