January 31, 2013 Standing Standard Project Committee (SSPC) 189.1 Re: AHRI Comments on Proposed Addendum be to ASHRAE Standard 189.1 Dear Members of SSPC 189.1: These comments are submitted by the Air-Conditioning, Heating, and Refrigeration Institute (AHRI). AHRI is the trade association representing manufacturers of heating, cooling, water heating, and commercial refrigeration equipment. More than 300 members strong, AHRI is an internationally recognized advocate for the industry, and develops standards for and certifies the performance of many of the products manufactured by our members. In North America, the annual output of the HVACR industry is worth more than $20 billion. In the United States alone, our members employ approximately 130,000 people, and support some 800,000 dealers, contractors and technicians. AHRI is opposed to the proposed language in addendum be to ASHRAE Standard 189.1-2011. We believe that the addendum is based on perception rather than technical justification. Several members of the committee believe that there should be zero emissions from gas-fired products within green buildings rather than considering the fact that stringent minimum safety standards already exist for these products, and that a certain level of analysis was conducted in order to establish those standards. If the committee wants zero emissions within a green building, it should also disallow people from inhabiting within a building, but that is an impractical solution. Rather than prohibiting the use of products, the committee should have considered and proposed levels that manufacturers could strive to achieve. In addition to indoor air quality, it is important that a product s utility and efficiency be considered within a standard. Members of SSPC 189.1 also ignored the fact that certain unvented heaters are not meant to be used as the primary heating source in buildings whereas others offer the most efficient means of heating in commercial and industrial applications. During a webinar of the Standing Standard Project Committee (SSPC) 189.1 on September 24, 2013, a member of SSPC 189.1 mentioned that the standard was not really intended for industrial buildings or warehouses. The committee s role is not to presume which buildings this standard can cover. At the very least, the committee should technically justify why the minimum safety standards associated with unvented heating products were ignored while developing this proposal. Simply stating that 189.1 is a green building standard and therefore no by-products of emission should be allowed in such buildings is not an appropriate rationale. The proposed addendum would lead to the prohibition of the following products from high performance green buildings: unvented infrared heaters, direct-fired heaters, and vent-free gas heaters. We would also like to note that the proposed language within addendum be does not adequately reflect the content within the foreword. Although the foreword claims to exempt direct-fired non-recirculating industrial heaters from the scope of this addendum, the proposed language does precisely the opposite. Such confusing information significantly hampers the
Page 2 of 5 ability of interested stakeholders to comment. The foreword also states that this proposed addendum would make the provisions of Standard 189.1 similar to the International Green Construction Code (IgCC). We do not agree with this statement. The proposed language within addendum be is significantly different from the IgCC language and adversely impacts products such as direct-fired heating/ventilation equipment and indirectly-vented infrared heaters. Section 1.a. of the standard states that the purpose of this standard is to balance environmental responsibility along with resource efficiency, occupant comfort and well-being. The key term here is balance. The standard does not specify how this balance must be achieved. Certain heating products, whether indirectly vented or directly vented can be used to achieve the balance stated within this section, especially in the area of improving the efficiency of the utilization of fossil fuels. Section 2.1.b of this standard states that part of the scope of the standard is to Address site sustainability, water use efficiency, energy efficiency, indoor environment quality (IEQ) and the building s impact on the atmosphere, materials, and resources. The proper application of certain heating products (indirectly vented or directly vented) can successfully meet the intent of this standard s scope. We believe that this proposed addendum has major implications on energy efficiency and indoor environmental quality (IEQ). Hence, in addition to undergoing a review by the full committee of SSPC 189.1, our comments should also be evaluated by Working Groups 7 (Energy Efficiency) and 8 (IEQ). Commercial-Industrial Direct-Fired Heaters This proposal fails to recognize a critical, fundamental characteristic of gas direct fired heaters used in various commercial and industrial applications. Specifically, direct fired heaters are part of the building s ventilation system. Gas direct-fired heaters do not add to the building s ventilation load. Rather the direct-fired heater is an essential component of the ventilation system that was designed for the building. The use of direct-fired heaters is addressed in Chapter 28 of the 2012 ASHRAE Handbook, HVAC Systems and Equipment. That chapter discusses units that are designed to condition ventilation air introduced into a space or to replace air exhausted from a building. It is further noted that these units may be used to prevent negative pressure within buildings or to reduce airborne contaminants in a space. When it comes to heating air, a gas-fired direct-heater performs the very function described in Chapter 28. Furthermore, since the units are direct-fired, the heating is done at the highest level of efficiency. As noted in Chapter 28, the ANSI Standards Z83.4 and Z83.18 address the ventilation function of these heaters and dilution concerns by requiring stringent limits on the potential contaminants (CO, NO 2 and CO 2 ) in the products of combustion. These limits are far below the Occupational Safety and Health Administration (OSHA) 8 hour exposure limits for these contaminants. Recognizing that ventilation is an inseparable aspect of the operation of direct fired heaters, it would be more appropriate to identify these products as direct fired heating/ventilation equipment. The mere existence of these standards and codes indicate that certified gas-fired heating products are appropriate for the successful design of all building types, provided the units are applied and installed per the manufactures instructions, and per the National Fuel Gas Code. In
Page 3 of 5 the case of 100% outside air non-recirculating direct-fired heaters (certified under ANSI Z83.4), the small heat input relative to the large ventilation air volume allows the product to maintain a high level of indoor environmental quality within a commercial or an industrial building. The temperature rise within such products ranges from 0 o F to 190 o F from ambient temperature, which means that such products bring in between 75 CFM 1000 CFM for every 15,000 Btu/h. The integral design of a single blower delivering both ventilation and combustion air for products covered by ANSI Z83.4 makes it impossible to operate without proper ventilation. In contrast, a gas range (which is currently exempted by the proposed addendum be) with a similar input rate brings in no ventilation air and relies on secondary systems to provide such ventilation, as noted by section 8.3.1.5.2 of the proposed addendum be. Furthermore, section 8.3.1.5.2 requires gas and electric ranges to be indirectly-vented via range hoods, so we fail to understand how SSPC 189.1 cannot use this exception as a basis to exempt direct-fired heating/ventilation equipment and indirectly-vented infrared heaters as well. One scenario for utilizing products that may emit flue products into the heated environment is for applications that are make-up air (or ventilation air) intensive, such as battery storage areas for UPS back-up systems, or in boiler or mechanical rooms where high levels of combustion and/or ventilation air may be required. In these applications, direct-fired heating/ventilation equipment may be the most efficient solution. Recirculating direct gas-fired heaters (certified under ANSI Z83.18) are also responsible for supplying enough fresh air to properly dilute their products of combustion. This ensures that the effluent concentration within the space is low when properly applied and operated in accordance with the manufacturer s instructions. Indirectly-vented Infrared Heaters The National Fuel Gas Code, ANSI Z223.1/NFPA 54, specifies minimum safety requirements for the design and installation of fuel gas piping systems in homes and other buildings. NFPA 54 addresses the requirements for the installation and operation of fuel gas piping systems, appliances, equipment, and related accessories, with rules for piping systems materials and components, piping system testing and purging, combustion and ventilation air supply, and venting of gas-fired appliances and equipment. In the case of indirectly-vented infrared heaters, NFPA 54 states that there needs to be a means for ventilation based on the heater rating and the following conditions: Natural or mechanical means shall be provided to supply and exhaust [combustion and ventilation air at a rate of] at least 4 ft 3 /min/1000 Btu/h (0.38m 3 /min/kw) input of installed heaters. Exhaust openings for removing flue products shall be above the level of the heaters. The implication that indirectly vented heating equipment is not appropriate for high performance green buildings in not accurate. In many situations, high and/or low intensity indirectly-vented infrared heaters, or direct-fired heating/ventilation equipment offer the most efficient solution to maximizing resource efficiency. For example, a large open storage area with a low occupant density within a building may not need to be heated or cooled to the levels of other areas of the same building. However, spot heating may be the best design option within these spaces in order to facilitate human comfort (i.e. a clerk at a loading dock area). In this case such products may be the most efficient means of heating even though they may not be directly-vented.
Page 4 of 5 Indirectly-vented infrared heaters and direct-fired heaters offer substantial energy savings in applications such as large industrial buildings, aircraft hangars, auto dealerships, auto service stations, manufacturing facilities and restaurant patio heaters. A provision that requires such products to be vented to the outside reduces energy efficient options for building owners, and reduces the product choices available in the marketplace. Chapter 16 of the 2012 ASHRAE Handbook for HVAC Systems and Equipment (SI Version) states the advantages of infrared heating within section 16.1 (titled Energy Conservation ). The section states that infrared heaters are effective means for spot heating and transfer heat directly to solid objects. Little heat is lost during transmission since air is a poor absorber of radiant heat. Section 16.1 also states that in radiant heating, the dry-bulb air temperature may be kept lower for a given comfort level due to increased mean radiant temperature. As a result, heat lost to ventilating air and via conduction through the shell of the structure is proportionally smaller, as is energy consumption. Infiltration loss, a function of dry-bulb air temperature, is also reduced. Infiltration and transmission heat losses are further reduced since the unique split of radiant and convective components in radiant heating help minimize air movement and stratification within the heated space. Due to the reduced fuel requirement associated with infrared heating systems, it has been noted that it is desirable for manufacturers of radiant heaters to recommend installation of equipment with a rated output that is 80-85% of the calculated building heat loss. Prohibiting the use of these products as an efficient form of heating as well as area and spot heating in large industrial applications is contrary to the intent of promoting the use of energy efficient products in green buildings. In conclusion, there is no need to restrict the use of indirectly vented heating products simply because a green building design is under consideration. The fact is that the inclusion of these products with other conventional heating and cooling products may offer the greenest solution for a green building design. Unvented (Vent-free) Combustion Heaters The following reasons further substantiate our opposition to this proposed addendum with respect to vent-free gas heaters, products that are typically installed in hotel lobbies, restaurants, remote spaces where supplemental heat is needed (e.g. warehouses and storage areas): 1. These products have input rates of 40,000 Btu/h, and are not supposed to be used as a primary source for heating. Section 10.23.2 of the 2012 National Fuel Gas Code (ANSI Z223.1/NFPA 54) requires that unvented room heaters be listed in accordance with ANSI Z21.11.2, Gas-fired Room Heaters Volume II, Unvented Room Heaters, and be installed in accordance with the manufacturers installation instructions. Sections 1.21.2 and 1.22.9 of ANSI Z21.11.2-2011 require that manufacturers indicate in their instructions and markings that these products are intended for supplemental heating only. 2. ASHRAE issued a position document (PD) on such products in January 2012. The document expires on January 25, 2015. The PD committee did not take any position on whether to include, or not, unvented combustion in any standard, nor did it take a position to ban those products in any way. One major recommendation in the PD is that more research is needed.
Page 5 of 5 3. There is a possibility of some indoor air quality (IAQ) research being conducted at the ASHRAE 62.2 level with respect to these products. We recommend that SSPC 189.1 refrain from taking any action on such products until the findings of this research are released. 4. Several studies have been conducted on unvented heaters. One independent study was conducted by risksciences, LLC, a scientific consulting firm. The study concluded that for the vast majority of homes in the U.S., vent-free gas heaters do not contribute to excessive indoor humidity. A copy of this study can be accessed here: http://www.ventfree.org/images/stories/files/final_ex_summary.pdf Another study was conducted to investigate the impacts of unvented gas heating appliances on NO 2 levels indoors in tight homes. The study concluded that for various regions within the U.S., the predicted NO 2 levels associated with the use of unvented gas heating appliances in tight houses met all short-term 1-hour indoor NO 2 standards that have been issued by various agencies. A copy of this study can be accessed here: http://www.ventfree.org/images/stories/files/vent_free_no2_modeling_study_final_sum mary_march_21_2013.pdf These studies have yielded positive results with respect to the performance of vent-free gas heaters within residential spaces. The fact that commercial building codes have more stringent ventilation requirements confirms that such products would perform even better with respect to indoor air quality in high performance green buildings. Furthermore, the instruction and marking requirements set forth in ANSI Z21.11.2-2011 state that manufacturers must specify the provisions for adequate combustion and ventilation air, which would be available in abundance within high performance green buildings. Additional information on vent-free gas heaters can be found here: http://www.ventfree.org/. Concluding Remarks We would like to reiterate that rather than prohibiting the use of the products mentioned in this letter, the committee should have developed a proposal that is technically justified. Although the proposed addendum was developed by the IEQ working group, it also has major implications on energy efficiency and those impacts should be extensively reviewed by Working Group 7. We believe that the reasons used to exempt gas ranges within the proposed addendum could have also been used as a basis to exempt the products discussed within this letter. Sincerely, Aniruddh Roy Regulatory Engineer Air-Conditioning, Heating, and Refrigeration Institute 2111 Wilson Boulevard, Suite 500 Arlington, VA 22201-3001, USA 703-600-0383 Phone 703-562-1942 Fax aroy@ahrinet.org