I'm going to try and give you all the info you need and probably more!
I live in Texas (College Station) and have buckling hardwood floors. My house was built in 1957is 1500 sq feet with 75% being pier and beam, the rest is concrete in converted garage and porch. The soil is clay. I have lived in the house for four years. The floors were refinished approximately five years before i bought the house. the first spring i lived in the house we had record setting rain, over 15". my contractor had framed in the crawl space with 2x2's and finished it out with 2x4's covered with a screen.this kept any water from draining out...which of course shouldn't be a problem. during a rain i realized there was water leaking under the wood on the crawl space so i removed the cover. i had a river of water running out from under my house for an hour. i had a foundation person come out and check things and he could see water marks and said it looked like i had 3-4" of standing water. he said that everything looked good otherwise...the water could have been there for as long as a month.
i do not have gutters d/t the large pine trees that are constantly dropping needles on my roof, and my inability to clean them. i do have a drainage problem and do get some standing water in one corner of the house. at this point i need you all to understand that i have a chronic illness that can be incapacitating and as i live alone it has kept me from getting repairs that i want to do in a timely manor so the point of all this is water around and under my house is nothing new.

in February i noticed that the wood floor in a five by five foot area near the wall in the middle of my living room were cupped. this is the side of the house that is pier and beam.
i was to ill to look into it. as the months went on the cupping spread to the entire living room. about four months from the start of the cupping the buckling started. the first few buckled areas were more like speed bumps, smooth and about three inches tall.the buckling at that time was only in the space that the cupping started near the wall in the center of the living room and did not go under the wall into the next room. slowly the cupping had started to spread to the next room (all the problems are over the pier and beam part of the house. there are hardwoods on the slab in the old garage that was done a long time ago as all details, trim, windows, wood floors etc. match the rest of the house. these floors have no problems)

we did have an unusually rainy spring/summer.

i had an inspector out and he confirms it is moisture with a meter. he notices the roof is sagging in one place which he feels is foundation shift, however my prepurchase inspector did not get on the roof and only briefly looked at the front of the roof and said it looked good so it could have always been like that, my prepurechase inspector didn't have a ladder.
I also have a wall that is bulging, but did not read moisture and the doors on either side of that bulge are do not open or close properly. this wall is in the converted porch room and there is beadboard on the walls. the wall which is drywall on the other side is not effected.

the new inspector looks under the house, but does not go under the house, and said it was wet under there and i needed to get gutters, regrade the yard, and have more air vents put around the house. at this point the buckled areas in the floor have gotten taller and longer, and there are at least two new ones.

i have a plumber out the next day to check for leaks since the main house supply line runs under the living room (all other water pipe bathrooms, kitchen etc are along the back of the house). he goes under the house, finds no leaks and says it is dry under the house.

i have a sewer line that appears to have been replaced since the clean out drain cap is plastic. i'm worried about a leak since the side walk it runs along is undermined and sunken. i have a camera run both directions with no leaks detected.

i have a city engineer and they just say it's not their fault as there are no water lines near the house.

I speak to a foundation person who says he has had a lot of calls this year about buckling floors sue to the rain. he does not come out.

the only changes in the house are a new HVAC unit placed last july. i went from a two ton to a two and a half ton per the recommendations of the installer. after the ac is installed i have all kinds of problems including the house smelling moldy which it never did before, condensation from one of the vents dripping on the floor, air leaking around the...don't laugh can't spell..flew. it was also supposed to have a multispeed fan and humidistat to help take moisture out of the air which it didn't, and it wasn't cooling properly. a carrier rep from Houston came out and looked and said the unit was running as it should. they also said part of the problem was that i needed more insulation in the attic so i had more blow in to R-19.
the floors are continuing to get worse. over four days the largest buckle comes up. it is at least six inches tall and the tongue and groove of the wood floor is exposed and pulled apart at least an inch. this one goes the length of the room. other ones are forming and old ones are getting worse.

because of the only change being the ac and insulation i have a different ac person come out to look at the system oh and i to keep the house cool d/t my health, around 65. i also have to keep the ac set at a low temp or it doesn't run enough and the air gets warm and humid.

the new ac company actually took pictures of my install to show their people how not to install a unit it was so bad. on thing they did was to run the gas line through the return air! so they are telling me that i need to have insulation put under my house, an inspector look at the unit and that i might have to rip the entire unit out and replace it. they look under the house with a flashlight (only the plumber has actually gone under) and they tell me that it is all wet and moldy under there and all the wood is rotting.
they also said i need to put insulation under the house.

i have a contractor out to look and give estimates. he doesn't think i need as many air vents as the inspector did, and that i need a third roof vent.

i have a friend who has his builder come out and he as everyone agrees it is a water problem. but he is unimpressed with the rain or drainage problem as they are not new. as he said this house has been standing here for fifty years and this never happened so something had to change. he does not feel it has anything to do with the joists.
he wants his ac people to look at my unit and his insulation person to look under the house. the problem is it has been two weeks since he has been out and i have not heard back. he is a high dollar builder who is doing this as a favor for a mutual friend. and in the time since he has been here the floors continue to get worse. i'm afraid that i will get a buckle in from of the front door and not be able to use the door.
I will say that along the back wall of the living room the floors are not as bad, and actually read dry when the inspector was out, but that is where the sun sets and it gets hot.

so i have many different opinions and the only thing anyone agrees on is that it is a moisture problem but nobody know from what...

HELP! does anyone have any ideas suggestions? i have already spent 600 to have all these people out and have not gotten anything fixed yet!

i have put a dehumidifier in the living room and don't know what is safe to set the ac on if it even makes a difference.

thank you in advance for any help suggestions
sorry for the novel