Water keeps running & overflows

if it fails to stop running only at the rinse part of the cycle it is probably in the timer as the solenoid valve has to cut the water off when the washer fills for the wash cycle too. fills for wash cycle and cuts off water, washes and drains, refills for rinse cycle and water just keeps running? does this every time you run it? that's in the timer. bad solenoid (water inlet valve) would keep running even on wash fill up. hope this helps.

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Your drain hose is pushed too far down into the drain so when you select the larger load sizes the water is being siphoned out as it goes in due to the pressure differential.

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Your pressure switch stops the water and allows it to start the next cycle. It's a switch either in the control panel or at the top of the tub with a small tube connected to it which goes down between the inner and outer tub. As the water level increases the air in the tube is compressed until there is enough pressure to make the switch stopping the water from filling. This tube can get clogged and the switch won't work. Remove the tube and clean it out. Blowing on the tube when it's still connected to the switch will make the switch if it's working and clear.

Water inlet valve

If it fills with water and starts the cycle and the water keeps running in then your water inlet valve on the back where the water supply comes in is sticking. It needs replacing.

If the water stops when the heater is not running then the humidifier is working fine. I know it seems like alot of water but that's how it's designed.

Jammed solonoid valve open position.....

Sounds like you've got a problem with the water intake valve(s). If it takes on water without water running in the sink, that is where I would look. If it happens when you use the sink, then I would also check your drain hose placement

Could it be ...this happens only when it is overloaded or the load is out of balance. Please clarify.

If this is not the case .. the water level hose running from the outside tank to the water level switch is likely not making a good seal (otherwise the water level switch itself is bad). Sometimes with age the hose forms a crack in it near or at the end where it connects. This could happen at either end of the hose. Also if you have removed the control panel recently (for any reason) you may have (not knowingly) pulled the water level hose loose from the water level switch. Just slide the hose back onto the tube of the switch before putting the control panel back in place and all will be fine after the first filling of the tub (it may take one filling cycle to build the needed vacuum back up in the hose). Unless of course in the process you have broken the tube off the switch where the hose goes on. In this case replace the switch.

This is a fill valve gone out