First of all, Carmen, I am not a plumber, so I can't comment on whether this is a problem. I take your word for this.
If it's really a problem, then yes, an inspector should have commented on it and alerted you to its risks.
I would first contact my Realtor, and develop a plan of approaching the problem.
This would include:
1. Contacting the original inspector and having them come out to the property to view the problem.
2. Contacting the previous owner to see if they were in any way aware of this issue. (this will probably need to be done through the original listing agent)
3. Talking to the company who did the plumbing work, assuming they are still in business. (This information will need to be obtained from the previous owner)
From that point, you can find out who will assist you in resolving the problem, with as little impact on your life, and wallet, as possible.
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