How do I vent a washing machine without hooking up to a vent stack or through the roof?
You must be asking about a mechanical vent. You can buy these in most hardware stores. They are not acceptable by the plumbing code, but in a pinch they are good. Don't hide them in a wall, in case you need to replace it, keep it accessible. Install it above the highest water level of the washer.
Here is a picture of the mechanical vent you need. Install it after the p-trap coming off a tee. Use a 1 1/2" female pipe adapter to screw it into. Use Teflon tape or dope on the threads. They cost under $5. Here is more info about the vent at Amazon.
Dave(Ask Dave) (About Dave)
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