Confined Space:

(Small Room, Closet, Alcove, Utility Room, Etc.)

A confined space is defined in the NFPA #54 as "a space whose volume is less than 50 cubic feet per 1000 Btu/hr (4.8 m3 per kW per hour) of the aggregate input rating of all appliances installed in that space." A confined space must have two combustion air openings. Size the combustion air openings based on the BTU input for all gas utilization equipment in the space and the method by which combustion air is supplied:

Using indoor air for combustion Using outdoor air for combustion

Louvers and Grills

When sizing the permanent opening as illustrated in figure 17, consideration must be taken for the design of the louvers or grills to maintain the required free area required for all gas utilizing equipment in the space. If the free area of the louver or grill design is not available, assume wood louvers will have 25% free area and metal louvers or grills will have 75% free area. Under no circumstance should the louver, grill or screen have openings smaller than ¼”.

Example:

Wood: 10 in x 12 in x 0.25 = 30 in2

Metal: 10 in x 12 in x 0.75 = 90 in2

Location

To maintain proper circulation of combustion air two permanent openings (one up- per, one lower) must be positioned in confined spaces. The upper shall be within 12 inches of the confined space and the lower opening shall be within 12 inches of the bottom of the confined space. Openings must be positioned as to never be obstructed.

Combustion air provided to the appliance should not be taken from any area of the structure that may produce a negative pressure (i.e. exhaust fans, powered ventila- tion fans).

Gas Vent / Boiler Exhaust

OUTLET AIR DUCT

BOILER

 

12in. MAX

PERMANENT

BOILER

 

OPENINGS

 

 

12in. MAX

 

12"

 

(300mm)

Instructions Rinnai E-Series

INLET AIR DUCT

Louvers and grills

10"

(250mm)

figure 17

Installation & Servicing

35

Page 35
Image 35
Rinnai E75CP, E110CP, E75CN, E110CN user manual Confined Space, Louvers and Grills, Location

E75CP, E110CN, E75CN, E110CP specifications

Rinnai is a leading name in the heating industry, recognized for producing highly efficient and reliable tankless water heaters. Among their popular models are the Rinnai E75CN, E75CP, E110CP, and E110CN, each designed to cater to various household needs and preferences.

The Rinnai E75CN and E75CP are both remarkable for their compact size and impressive heating capabilities. The E75CN is a natural gas model, while the E75CP runs on propane. These units are designed to deliver a maximum flow rate of up to 7.5 gallons per minute, ensuring that multiple fixtures can be used simultaneously without a dip in performance.

Both models incorporate advanced temperature control technology, allowing users to set their desired water temperature with precision. The units feature a durable heat exchanger, constructed from high-grade stainless steel, which not only promotes longevity but also helps in preventing corrosion. Additionally, they come with built-in safety features, such as freeze protection and an overheat cut-off system, ensuring safe operation in varying conditions.

Moving on to the Rinnai E110CP and E110CN, these tankless water heaters are designed for larger households with higher hot water demands. The E110CP operates on propane, while the E110CN utilizes natural gas. These units deliver a maximum flow rate of up to 11 gallons per minute, making them ideal for simultaneous use in multiple bathrooms, kitchens, and laundry rooms.

The E110 models showcase Rinnai's Smart Technology, which optimizes energy consumption by adjusting the heating output based on the demand. This not only maximizes efficiency but also significantly reduces energy costs. They are equipped with digital controls and diagnostics, providing users with real-time information and the ability to troubleshoot easily if any issues arise.

In terms of installation, all four models are designed for versatility. They can be installed indoors or outdoors, giving homeowners flexibility based on their space and preference. With their compact design, these units require less space compared to traditional tank heaters, making them a suitable choice for modern homes.

Overall, Rinnai's E75CN, E75CP, E110PC, and E110CN models represent cutting-edge technology in tankless water heating. Their efficiency, safety features, and advanced technology make them an excellent choice for homeowners looking to upgrade their hot water systems. With Rinnai, users can enjoy the convenience of continuous hot water without sacrificing energy efficiency.