Service Manual

Page 58
Figure 49 – Heat Exchanger Cleaning
Heat Exchanger Fin Coils
Inspect the heat exchanger fin coils for soot build-up or blockage. If there is evidence of soot build-up or
blockage, the heat exchanger should be removed by a professional and cleaned thoroughly. Soot is an
indication of incomplete combustion and a clear sign of a serious problem. Venting, gas pressure, and
flue gases should be examined to determine the cause of the problem. Damage to the water heater
caused by incorrect installation or adjustment are not covered by the manufacturer's warranty
Take care not to damage the seals that ensure tightness between the heat exchanger, the heat cell,
and collector and ensure correct clearing and alignment of the fins.
In hard water regions it may be necessary to descale the heat exchanger body, using a proper
descaler. Fill the heat exchanger with the descaling solution and let it act until the solution stops
bubbling. Drain and thoroughly wash out the exchanger with clean water.
Warning: Acid/water solutions must be used with extreme caution. Take care not to splash on to the
skin or into the eyes. Wash any affected areas with large amounts of cold water and seek medical
advice.
Figure 50 – Heat Exchanger Descaling
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