I cannot find the correct check valve (non-return valve) for my dishwasher. The one that Bosch lists for it (Part #00165262) is less than half the size of the one I removed; also of a different colour and texture. (I can provide a picture if I have an email address to send it to or upload-site URL to upload it to.) The person at the parts store says that the valve I took out just changed from age, and swelled up, but that seems very unlikely given the scale of the differences. I think it's possible that this model, possibly for geographical reasons, has had more than one check valve. I have talked to Bosch Customer Support. No help.
Answer Hello Randy,
The non-return check valve can indeed swell from age, rinsing the dishes before putting them into the dishwasher, and/or excessive soap usage. Please do not take offense to this as it is not at all meant to sound like I am blaming it on you. Think of it this way: The chemical reaction from the detergent is a harsh chemical reaction. The reactant in the detergent is geared toward attacking food particles. If the dishes are scraped but not rinsed as recommended, there is enough food particles to occupy the detergent. If the dishes are rinsed first, the detergent will actually attack the rubber seals in the dishwasher, patterns on plates, and will actually cause the silverware to go grey because there is nothing else to occupy it. Since there are no other size check valves in this unit, I would have to assume the seal has swelled and malformed. I would order this part and try it. You can always return it if it will not fit properly.
What is the purpose of the check valve WD1X5488? Does it affect the cleaning process? Thank you
Answer Hello Brian. The check valve is used to prevent water from flowing back into a location where is should be drained from. If it is bad, it can allow dirty water into the machine.