The figure below shows the two main families of acetylcholine receptors: muscarinic and nicotinic. In structural terms, muscarinic receptors are G-coupled protein receptors, while nicotinic receptors are ligand-gated ion channels. They can be found on both sides of the synaptic cleft (presynaptic and postsynaptic).
After the pressure drops below 40 psi, the electrical switch turns on the pump and the pressure in the tank increases. Any failure in any component or loss of electricity can cause a well to suddenly stop producing water when a faucet is turned on.
Quick Answer. The most common cause of brown well water is iron contamination. A sudden change in water color means that the contaminant is newly introduced to the well, and it may be caused by industrial contamination, rusty plumbing fixtures or natural iron leaching from the ground. Continue Reading.