CleaverBrooks ClearFire CFH, Operation, Service And Parts Manual, Page: 8 / 120

Chapter 1 — Introduction
1-2 Part No. 750-295
1.1-MODEL CFH FEATURES AND BENEFITS
Compact Firetube Design
The Model CFH boiler is a compact horizontally fired firetube boiler. The extended heating surface tubes
provide for very high levels of performance in a compact space. The Model CFH boiler is designed to fire
natural gas or LP gas. Dual fuel arrangement (natural gas and propane) is also available.
High Efficiency
With the extended heating surface provided by the patented AluFer
®
tube design ( Figure 1-1 ) the Model
CFH has a nominal fuel to steam efficiency of 85%.
Advanced Construction
Constructed to ASME standards and utilizing AluFer
®
Tube
technology in a single-pass design, the Model CFH Boiler will
provide many years of trouble free service. Single-pass design
provides excellent thermal shock protection.
Ease of Maintenance
The enclosure is readily removable for access to all key burner
components. A hinged door on the control panel provides access
to all controls.
Quality Construction
ASME construction ensures high quality design, safety, and
reliability.
ISO 9001 certified manufacturing process ensures adherence to
the highest manufacturing standards.
Full Modulation
The burner and combustion fan modulate to provide only the amount of heat required, providing quiet and
efficient operation under all conditions.
Premix Technology
The Model CFH Boiler utilizes “Premix” technology to mix both fuel and combustion air prior to entering the
firing chamber. This technology provides clean, efficient combustion with very low emission levels.
1.2-THE MODEL CFH BOILER
Firetube boilers are rated in boiler horsepower (BHP), which should not be confused with other horsepower
measurements (1 BHP = 33,475 BTU/hr.).
Steam boilers are designed for low pressure or high pressure applications. Low pressure boilers - those
bearing the ASME “H” stamp - are limited to 15 psig maximum design pressure, and are typically used for
heating applications. The CFH minimum operating pressure for acceptable steam quality (99% dry steam)
is 6 psig.
CFH high pressure steam boilers are used for a variety of applications requiring high pressure steam in a
compact footprint, and have a design pressure of 150 psig.
Steam boilers are defined according to design pressure and operating pressure. Design pressure is the
maximum pressure used in the design of the boiler for the purpose of calculating the minimum permissible
thickness or physical characteristics of the pressure vessel parts of the boiler. Typically, the safety valves
are set at or below design pressure. Operating pressure is the pressure of the boiler at which it normally
Figure 1-1 AluFer
®
tube cross
section