Blower Speed Control; Burner Assembly - A.O. Smith Cyclone XL 100 Series Service Handbook

Commercial gas water heaters

Table of Contents

The CCB monitors a feedback signal from a sensor that is installed on the blower. The CCB interprets the pulse signal from the sensor

and then sends a signal to the blower to produce the proper blower speed and input.

These models are capable of modulating their input rate. Therefore, the RPM readings can be in between the Heating Speed and

Minimum Modulation Speed RPMs. The input rate should be verified with the water heater operating at full input rate.

Table 2 and Table 3 list the RPMs for each model at high heating speed, low fire speed, and ignition speed.

Nateral Gas

BTHS 750

BTHS 1000

* Note: ±10% High Heating Speed RPMs are based from the Nominal "Certification" Heating Speed RPMs.

Propane Gas

BTHS 750

BTHS 1000

* Note: ±10% High Heating Speed RPMs are based from the Nominal "Certification" Heating Speed RPMs.

The Burner is a radial design burner with a steel fiber jacket on the outer surface and is part of a larger Burner Assembly. Figures below

show side views of the complete Burner Assembly removed from the water heater with key components identified. See the exploded

view in Figure 4 (page 7) also.