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P trap directly into main stack


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Had an inspection today with a p trap plumbed directly into the main stack serving the furnace/A/C condensation line. The house was slab on grade built this year. Anything wrong with the configuration? If so, any code cite would be greatly appreciated. Thanks



Edited by greyboy39
Punctuation error
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It's an indirect drain for non-potable, clear waste water. It's ok. The air gap prevents a sewer back up from fouling the heating/ cooling equipment. The only draw back may be if the heating/ cooling system goes unused long enough for the trap water to evaporate and lose the seal. That's a stretch though.  

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32 minutes ago, greyboy39 said:

Thanks for the clarification Chad. I initially thought it could potentially back siphon as a result of being too near the main stack. 

The air gap isn't big enough. I shouldn't have said "OK".   Honestly, I thought you were asking if it was OK because it was an indirect connection. I just spent 7 or 8 horrible minutes reading the plumbing code. It's all in chapter 8 of the IPC. I'll email it to you if you want.


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