This is 18 year old Heil furnace.
The exhaust blower did not turn so I replaced it with a new one. The new one made splashing noise so I thought it had a problem and replaced it with another one. I cleaned all drain tubes. The water comes
into the blower's intake from the secondary heat exchanger (?) and leaves through the drain pipe. BUT the blower's turbine makes splashing noise. There is no drain in the exhaust blower. There is no drain in the secondary heat exchanger. But the noise is ubnormal. Otherwise the furnace works . Please, advice. Thanks!