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Bosch Tankless Whistling Problem
I have an Aquastar 250NG Bosch tankless water heater that won't stop whistling and it doesn't appear to be that the inlet line size is too small or the venting is incorrect.
From the research I've done, it seems that the valve needs to be adjusted. Has anyone done this and succesfully eliminated the noise? I've read about plenty of people having the same difficulty with this noise, but very few success stories.
I guess what I'm really looking for is someone who has personally beat this problem and the specifics on how to do it before I either spend the time adjusting the system further or hiring someone to come in and replumb or pipe the unit. If it's something that can't really be addressed, I'll just scrap the whole idea and get a new unit, but I'd really rather not spend the cash as money is tight.