All installations and services must be performed by qualified service personnel.

C.ADJUSTMENT OF BTU INPUT RATE:

The orifice for this furnace was sized: 1) for natural gas having a heating value of 1025 BTU per cubic foot and a specific gravity of .65, or 2) for liquefied propane gas with a heating value of 2500 BTU per cubic foot and a specific gravity of 1.55. The information plate inside the furnace vestibule will specify which gas your furnace is orificed for. If the furnace is installed at an altitude that is more than 2,000 feet above sea level, it is mandatory that the input to the burner be reduced 4.0% for every 1,000 feet that it is above sea level. If the furnace is installed at an elevation of 5,000 feet, its input must be reduced 20.0%. Example: a furnace rated at 75,000 BTU at sea level must be reduced to a firing rate of 60,000 (75,000 x .80 = 60,000) at an elevation of 5,000 feet. If the furnace is installed at an elevation of 2,000 feet or less, no reduction in input is required. Your gas supplier or Thermo Products will supply you with the correct orifice sizing information.

To check the input of your natural gas furnace, allow the unit to operate for 10 to

15 minutes and proceed as follows:

1.Call your gas supplier and ask for the BTU content (heating value) of one cubic foot of the gas, supplied to the installation area. An alternate approach is to assume a value of 1025 BTU/Cu Ft which is the national average.

2.With all other gas appliances turned off and using a stopwatch, clock the time required for the (small) dial on the gas meter to make one full revolution. The meter dial will state the cubic feet of flow for one revolution usually one, two or five.

FORMULA: BTU/Cu Ft x Number of Cu Ft x 3600 Seconds = Input BTU/hr Seconds for one revolution

EXAMPLE: 1025 BTU/Cu Ft x 2 Cu Ft x 3600 = 73,505 BTU Input 100.40 Seconds

Check the model number of the furnace, the input rate, the type of gas, and the manifold pressure on the rating label located in the burner vestibule. If using the above example, the furnace is a CMA2-75N model and the input rate is 73,505 BTU/hr. The input rate would be acceptable because it was within + 2% of the listed input of 75,000.

3.Make sure that the gas supply pressure to the furnace is within the allowable range of 5.5" to 14" WC pressure on natural gas and 11.0" to 14.0" WC on propane gas. The pressure to the furnace must be checked while the furnace burner and any other gas appliances on the same supply system are operating, using the 1/8 in. NPT manifold pressure tap.

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Thermo Products CMA3-75D36N, CMC1-50DV3N, CMC1-50D36N, CMC1-75D36N, CMA3-50D36N, CMC1-75DV3N Adjustment of BTU Input Rate
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CMC1-75DV3N, CMA3-75D36N, CMA3-50D36N, CMC1-75D36N, CMC1-50D36N specifications

Thermo Products offers a versatile range of heating solutions that cater to various industrial and commercial applications. Among their popular models are the CMC1-75DV3N, CMC1-50DV3N, CMA3-50D36N, CMC1-50D36N, and CMC1-75D36N. Each model is engineered to deliver efficient performance and durability, making them ideal for meeting diverse heating needs.

The CMC1-75DV3N is tailored for high-capacity heating requirements, featuring advanced heating technology that ensures rapid and consistent heating. Its robust design includes high-efficiency burners, and the unit is built with durable materials for extended lifespan. This model is equipped with integrated safety mechanisms that prevent overheating and ensure reliable operation.

In contrast, the CMC1-50DV3N is designed for medium-sized applications, prioritizing both efficiency and cost-effectiveness. It includes automated controls to optimize energy usage while maintaining consistent temperature outputs. Its compact footprint makes it suitable for installations with space constraints, without compromising on heating performance.

The CMA3-50D36N model introduces enhanced energy management features, offering dynamic heating solutions. This model leverages advanced thermal technologies that aim to reduce energy consumption while maximizing heating output. Its versatile installation options allow users to adapt the unit to their specific space requirements seamlessly.

The CMC1-50D36N and CMC1-75D36N models are recognized for their adaptability across various applications. The CMC1-50D36N specifically caters to smaller heating needs, while the CMC1-75D36N serves larger spaces. Both units come equipped with user-friendly interfaces that simplify operation and adjustments, allowing for precise temperature control.

All models feature high-quality insulation and construction, helping to minimize heat loss and enhance system efficiency. They are designed with maintenance in mind, ensuring easier access to key components for service and repairs.

Through the incorporation of customizable settings, these models can suit the unique requirements of different environments, whether it be industrial facilities, commercial spaces, or residential buildings. With Thermo Products' commitment to innovation and quality, these heating solutions exemplify reliability, making them a solid choice for anyone in need of efficient heating technology.
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