Natural Draft Vertical Venting System Installation

Natural draft venting uses the natural buoyancy of the heated flue products to create a thermal driving head that expels the exhaust gases from the flue. The neg- ative draft must be within the range of –0.01 in. to –0.08 in. WC as measured 12 in. from the appliance flue outlet to ensure proper operation. Vent material must be listed by a nationally recognized test agency.

The maximum and minimum venting length for Category I appliance shall be determined per the lat- est edition of the NFGC (U.S.) or B149 Installation Code (Canada).

The diameter of vent flue pipe should be sized accord- ing to Part 11 of the latest edition of the NFGC (U.S.) and part 7 and appendix B of the B149 Installation Code (Canada). The minimum flue pipe diameter for conventional negative draft venting using double-wall B type vent is 4” for HD101 and HD151, 5” for HD201, HD251 and HD301, and 6” for HD401.

NOTE: Vent Adapter will have to be used to connect B vent to the unit.

The connection from the appliance vent to the stack must be as direct as possible and shall be the same diameter as, or larger than the vent outlet. The hori- zontal breaching of a vent must have an upward slope of not less than 1/4 inch per linear foot from the heater to the vent terminal. The horizontal portions of the vent shall also be supported for the design and weight of the material employed to maintain clearances and to prevent physical damage or separation of joints.

Natural Draft Vertical Vent

Termination

The vent terminal should be vertical and should termi- nate outside the building at least two (2) feet above the highest point of the roof that is within 10 feet. The vent cap should have a minimum clearance of four (4) feet horizontally from and in no case above or below (unless a four (4) foot horizontal distance is main- tained) electric meters, gas meters, regulators and relief equipment. The distance of the vent terminal from adjacent public walkways, adjacent buildings, open windows and building openings must be consis- tent with the NFGC, or in Canada, the B149 Installation Code for Gas Burning Appliances and Equipment. Gas vents supported only by flashing and extended above the roof more than five feet should be securely guyed or braced to withstand snow and wind loads.

CAUTION: Listed vent cap terminal must be used and sized adequately to evacuate the flue products from the heaters.

Natural Draft Vertical Venting with Common Venting System, Category I Appliance Only

Manifolds that connect more than one heater to a com- mon chimney must be sized to handle the combined load. Consult available guides for proper sizing of the manifold and the chimney. At no time should the area of the vent be less than the area of the largest heater exhaust outlet.

WARNING: Vent connectors serving appliances vented by natural draft shall not be connected into any portion of mechanical draft systems operating under a positive pressure.

CAUTION: Vent connectors for natural draft venting systems must be type “B” vent or better.

Common venting systems may be too large when an existing unit is removed. At the time of removal of an existing appliance, the following steps must be fol- lowed with each appliance remaining connected to the common venting system placed in operation, while the other appliances remaining connected to the common venting system are not in operation.

a)Seal any unused opening in the common venting system.

b)Visually inspect the venting system for proper size and horizontal pitch and determine there is no blockage or restriction, leakage, corrosion or other unsafe condition.

c)Insofar as is practical, close all building doors and windows and all doors between the space in which the appliances remaining connected to the com- mon venting system are located and other spaces of the building. Turn on clothes dryers and any appliance not connected to the common vent sys- tem. Turn on any exhaust fans, such as range hoods and bathroom exhausts, so they will oper- ate at maximum speed. Do not operate summer exhaust fan. Close fireplace dampers.

d)Place in operation the appliances being inspected. Follow the manufacturers instructions for lighting

26

Page 26
Image 26
Raypak HD401, HD101 manual Natural Draft Vertical Venting System Installation, Natural Draft Vertical Vent Termination

HD101, HD401 specifications

Raypak is renowned for its commitment to high-quality heating solutions, with the HD101 and HD401 models standing out in their product range. These units are designed specifically for commercial applications, providing reliable and efficient hydronic heating systems. The HD series embodies innovation while addressing the unique demands of larger spaces.

One of the main features of the HD101 and HD401 is their stainless steel construction, which ensures increased durability and resistance to corrosion. This design choice enhances the longevity of the units, making them ideal for various installations in commercial or industrial settings.

Both models are equipped with a high-efficiency heat exchanger that maximizes heat transfer while minimizing energy consumption. This feature is particularly significant in today’s environmentally conscious market, as it contributes to lower operating costs and reduced carbon footprints. The heat exchangers are engineered for easy maintenance, offering simplicity when service is required.

In terms of technology, the HD101 and HD401 include advanced digital controls that allow for precise temperature regulation. This user-friendly interface enables operators to easily manage and monitor heating parameters, facilitating optimal performance and energy management.

The models also feature modulating burners that adjust their output according to the heating demand. This capacity for modulation results in smoother operation and an overall increase in efficiency, as the burners can maintain consistent temperatures without excessive energy use.

Another noteworthy characteristic is their compatibility with various control systems, including BMS (Building Management Systems). This adaptability allows for seamless integration into existing infrastructure, providing users with greater versatility and control over their heating environments.

Both the HD101 and HD401 come with advanced safety features, including flame rollback protection and pressure monitoring, ensuring safe operation even in demanding conditions. Additionally, their compact design allows for easy installation in limited spaces while still providing powerful heating capabilities.

Ultimately, the Raypak HD101 and HD401 are exceptional choices for those in need of high-efficiency commercial heating solutions. With their robust construction, advanced technology, and user-friendly features, these models promise to deliver reliable performance and energy savings for years to come. Whether for a large facility or a specific industrial application, they stand ready to meet the heating challenges of today’s commercial landscape.