Lisa,
I think it is time to consider the fact that you have purchased an asset that will require maintenance, sometimes costly maintenance, and not a new car.
A home warranty is universally known to professional investors as "toilet paper". It's a sham peddled by builders and fresh out of school RE agents as a way to make first time home buyers feel "secure" in their decision to leverage everything.
Some of the buildings that I manage are over 120 years old.. and they leak.. and sometimes ONLY when the moon is in line with the sun and it is 6:00 with a south wind at 22 miles an hour... It can take even a great contractor much time to figure out "what the hello is going on here?".
In one case, I had a new $120,000 roof put on a medical center.. Only to have it leak in the same spot as it did before.. It took 3 additional roofers to find the root cause.
What I am trying to say is that what you are experiencing is NORMAL, and sometimes, owning a hunk of RE costs a few bucks for which coverage is not available.
If you really believe that some form of sub-standard building process was used to build this home, I would suggest you HIRE a qualified professional to not only diagnose and repair the problem, but to also give you a report, in writing, as to why the "item" failed.. Then submit a claim to the original builder.
But know this... At some point, all these insurances, policies and warranties WILL expire and you will be faced with the fact that you have purchased a large piece of responsibility that YOU will have to deal with, and pay for.
Sean
--76.105.xx.xx