Do they freeze?

With correct installation, and assuming that the electricity is operating, the answer is no. If a Ritchie fountain is frozen, it is because something is defective, a poor installation, or the application is not correct. The most common cause of freezing is a heater that has burned out, or a thermostat that has failed. If it is a Thrifty King CT unit that is being used without heat, it can be a poor installation that is allowing cold air to get underneath the unit, incoming water that is below 42 degrees, or not meeting the minimum head requirements for using these units. A majority of the time when a unit is not working in cold weather, it is at the valve. The supply line touching the side of the riser tube, which causes the water to slush up and not go through the valve, usually causes this. This is seldom a problem and will not happen with correct installation.