Effects of 2″ to 3″ PVC dry drain pipes through crawl space
Good evening. I have a 2,600 SF home that has 900 SF crawl space under half of it. The builder placed all the overflow type drains (next to water heater/washer, next to my mechanicals, etc, to run to daylight into my far yard. These don’t have water traps because they run to daylight I suppose and rarely if ever have drain water in them.
My house does not use A/C and in winter we currently use a large indoor wood burning stove and supplement cold rooms with electric oil radiant heaters, as-needed.
What are the effects of 4 to 5 two-inch diameter PVC drain pipes leading to larger 3″ pipes that find daylight, without water traps?
Should I leave it this way?
Can or should I install a large check valve in the two 3″ pipes they feed into the yard, to block outdoor air from sucking into house? The 3″ open drain closest to house foundation (2′ exact) seems like air is going into it, toward the house.
Not sure if the fresh air is good or bad, especially since I burn wood in a modern EPA stove. We also have a gas water heater chimney stack and another small gas stack for a wall heater we never use. And two roof vented bathroom exhaust fans. Man, all this seems to be a lot of holes to fill. Good or bad?
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