Water in the heating chamber will cause your heater to make these sounds. If your water is cold, it will create condensation inside of the heating chamber. Another way water would get into the heating chamber is if your heat exchangers are leaking. Id check to make sure that heating chamber is not full of water, if theres any real accumulation of water, 2" or more, inside that chamber, the exchanger needs replacing. Otherwise, it sounds like condensation.
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Water in the heating chamber will cause your heater to make these sounds. If your water is cold, it will create condensation inside of the heating chamber. Another way water would get into the heating chamber is if your heat exchangers are leaking. Id check to make sure that heating chamber is not full of water, if theres any real accumulation of water, 2" or more, inside that chamber, the exchanger needs replacing. Otherwise, it sounds like condensation.