Burnham `A' `B' `C' `D' `E manual CHG Site Glass & Burner, Boiler Operations, Premix Technology

CHG Site Glass & Burner

The flame can be continuously modulated from an orange glow to a full blue flame.

The burner is located on the top of the heat engine forcing the heat down while the water flows upward. This allows the condensation to drain down and away from the boiler.

Cutaway view showing actual water flow path.

Supply

Manifold

Return

Manifold

Negative regulated gas valve with factory set outlet pressure.

Venturi

Variable

Speed

Blower

Boiler Operations

The CHG castings incorporate a multi-pass water flow with the return water entering the lower manifold and progressing upward to the sup- ply manifold. This counterflow from bottom to top provides for maximum heat transfer while the serpentine pattern offers low pressure drop. Each section’s water flow is independent with no port connections between sections. The supply and return manifolds are designed to balance the flow across all sections.

Premix Technology

CHG boilers utilize a pre-mix combustion assem- bly that includes a modulating gas valve, vari- able speed blower and a venturi to provide an optimal fuel/air mixture to a stainless steel mesh burner. Together these components accurately and efficiently help control the fully modulating combustion process which automatically adjusts the boiler’s firing rate to match your heating needs.

Domestic Hot Water

Abundant domestic hot water is available with a matching Alliance indirect-fired hot water heater. Select from several sizes to meet your specific needs. In addition, the CHG boiler control module

is preset for domestic hot water priority and set point temperature.

Boiler	Horizontal	Vertical	Vent
Model	Vent Max.	Vent Max.	Diameter
CHG150	55 ft.	49.5 ft.	3 in.
CHG225	55 ft.	47 ft.	4 in.

Boiler Control Module & Outdoor Reset

The MCBA microprocessor control manages all boiler functions including supervising the com- bustion process and monitoring key operating functions. Included is a digital display that can provide detailed boiler information as well as be an invaluable service and troubleshooting tool.

The MCBA module stores set points for boiler and domestic hot water supply temperatures, and monitors supply and return water tempera- tures, flue gas temperature, the flame sensor, and the included outdoor reset. The boiler con- trol module allows for continuous modulation (firing rates) by varying the combustion fan speed.

CHG Venting

The CHG incorporates a sealed combustion system that uses outside air for combustion and the safe and proven AL29-4C stainless steel ma- terial for venting the exhaust. Both horizontal (“sidewall”) and vertical (“through-the-roof”) venting options are available.