Seminar 6 (Intermediate)
Challenges Venting High Efficiency Appliances
Track: HVAC&R Systems and Equipment
Sponsor: 6.10 Fuels and Combustion
Chair: Thomas Butcher, Ph.D., Brookhaven National Laboratory, Upton, NY
Larry Brand, Gas Technology Institute., Davis, CA
High efficiency gas fired furnaces, boilers and water heaters are generally installed with Category IV venting systems – positive pressure and condensing. In many retrofit cases, especially in multistory systems, the access to the roof for vent termination is not possible – an existing B vent may be installed in the chase or existing chimney and common-venting is not permitted. A sidewall vent is the only option, but there are restrictions. This presentation reviews the restrictions on sidewall venting in several national and local codes and investigates the potential for ice formation on sidewalls.
Tim McNulty, U.S. Draft Co., Fort Worth, TX
This presentation reviews the practice of common venting condensing or near condensing gas-fired appliances with respect to current ASHRAE guidelines, appliance manufacturers’ recommendations and code requirements. Although national guidelines have been developed for common venting Category I and draft hood-equipped appliances, there is no national standard for common venting condensing or near condensing appliances such as Category II and IV appliances. This presentation focuses on the current chimney design methodology along with the limitations as well as good practices related to common venting Category II and IV appliances.
Attend a Committee Meeting
ALL ASHRAE committee meetings, including this TC’s meetings at the Winter and Annual Society conferences, are open to the public at no cost nor is conference registration required. Interested visitors, local chapter members, and potential new TC members are always welcome. However to attend technical program sessions sponsored by the TC will require registration and payment of any applicable fee.
Participation in an ASHRAE TC provides the opportunity to grow professionally and to contribute to the advancement of HVAC&R within an international organization recognized for shaping the future of the built environment through research, standards writing, publishing, and education.