Condensation; Spare Parts - A.O. Smith BFM 30 Installation Instructions Manual

2.10 Condensation

If the water heater has been filled with cold water or if
the hot water usage has been very high, normally
condensation of the flue gasses will occur on the cold
sides of the combustion chamber and the flue tubes.
The water drops will fall on to the burner bed which can
cause a hissing sound. This is normal and will
disappear as soon as the water heater has reached its
operating temperature again.

2.11 Spare parts

To order spare parts, it is important to state the water
heater type, model and the complete serial number.
Figure 19 - Maintenance anodes
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