where i work is a state operated girls school. mostly troubled teens and drug addicted girls live and study there trying to turn their lives around. the closest comparison i can think of is a corporate retreat camp. they have a huge rock climbing wall--six stories. it has a zip line from the top that careens across the forest. there are three cabins, two class rooms, a vocational building and several support ancillary buildings. it is located ten miles from nowhere on a winding road surrounded by mark twain national forest.
there is a huge well that supplies the entire complex. no one claims that they know how the well and pressure tank works--even the local pump/well company. it is not a standard system since the pressure tank is huge and doesn't have a bladder. any way i have been trying to wrap my brain around the thing since it has been causing problems for quite some time. i think that i have figured it out. the tank has to be filled with air and water at some ratio that i don't know. the water is there for obvious reasons--to flush toilets and wash hands. the air is there to compress and expand maintaining a reasonable pressure for the system so that the pump doesn't have the run continuously--it would wear out quickly otherwise. since there is no bladder, a rubber barrier separating the water and compressible air pocket, the air slowly integrates under the higher pressure into the water and the tank ends up filled with just water. there is a compressor attached to the system to add more air in the event the water level gets too high in the tank--causing the pump to cycle. the part that isn't obvious is that there seems to be a float with a mercury switch that decides if the compressor or the pump should come on to add to the tank when there is water usage. the other issue is that the ozarks have incredibly hard water--off the charts. lime build-up causes water heaters to fail early and shower heads to clog. i am assuming that (if this float exists) the float is exposed to the same hard water that causes all the other problems. if so, the float might need some cleaning and mechanical encouragement to preform its task.
anyway, i giggled that switch until it worked loosely and things seem to be working fine now. i could take the float and switch apart but i am afraid that there would be a million little springy parts that would fly into my face as i took the cover plate off the unit. so for now, i'll just giggle the switch making sure that it moves freely occasionally and wait until that no longer solves the problem.