I noticed last night that the relief valve on the pressure tank from my well sprayed a bunch of water all over the floor. It wasn't a leak; it appears to have done so because the pressure got too high. At least, that's my guess. It hasn't happened again.
Any idea why the pressure would shoot up? We're in the midst of a drought...
The pressure tank could have become waterlogged (the air cushion lost and/or absorbed into the water)..
Should that happen, pressure can become erratic, and can go quite high if the water heater is heating the next tankful of water which wil expand slightly.
To recalibrate the pressure tank, turn off the pump and also the water heater. Open some cold faucets. :Slowly pump air into the valve on top of the pressure tank, maintaining at least 5 pounds until water stops flowing from the open faucets. Then set the tank pressure to the desired pressure, which is usually about 2 pounds less then the pump turn on pressure.
Turn the pump back on, wait for water to flow from both an open hot faucet and an open cold faucet. Then turn off the faucets and turn the water heater back on.
Stop wasting time re-adjusting the pattern. Have several lawn sprinklers, one for each pattern.