I have a Bosch dishwasher and it worked perfectly for 12 years, but yesterday I found a problem: waste water does not go out from the machine in the whole volume. In order to find out reason I disconnected drain hose from the waste line and started the heavy cycle. I have seen rotated part and strong water dropped down as usual, but no one water past through the drain hose from the machine when the cycle was finished. Conclusion: the water comes in but does not pump out. You have part # APZ826384 (Circulation Pump) in your stock but I'm not sure that if I will change it that it will help. Is it reliable to change this expensive part by myself? Thank you
Answer Hello Mark,
If the unit will fill with water and circulate it but will not drain out, the drain pump or a clogged filter is the usual cause. The drain pump can run and be bad. You see, the drain pump impeller is plastic and the drain pump motor shaft is stainless steel. It can separate from the motor shaft and the motor will run and the impel will turn but is incapable of pushing the water out. I have also found in units that have been in place for a long time can have an accumulation of grease in the lower parts of the system to include the drain line. If there are no clogs, the drain pump will solve the issue. The original drain pump has been dis-continued and you have to access the drain pump to determine the correct replacement as follows: If your original drain pump has 9 impeller vanes order 00642239 and 00623143. If your original drain pump has 4 impeller vanes order 00642239 and 00623143.