This is known as the Ritchie water seal and is patented. The water in the grooves creates an airtight seal to disallow cold air entering the valve chamber. Some people will fill this groove with vegetable oil for easier removal in the freezing months. Without this, we would have to use a gasket. It has been proven that when accessing a unit in winter that has a gasket, the gasket will come apart and have to be replaced.
Immersion Heaters are warranted for one year. We recommend taking this heater out at the end of the heating season, cleaning it, and storing it until the next heating season. We know of customers that had multiple heating seasons with this heater by doing this. If left in, this heater can have mineral deposits build up on it. These mineral deposits will create a hot spot and the heater will burn out.
Ritchie Thrifty King units, when used in the right application, do not require electricity. All other units, in freezing conditions, require electricity for the heating system. Ritchie recommends electric service on any new installation, including Thrifty King installations. If heat is needed later on, the electrical service is there. WaterMaster and CattleMaster are available with constant flow for use without electricity.
This varies depending on which unit you are using. Immersion heaters come on around 45 degrees Fahrenheit and go off at around 60 degrees. The disc thermostat is preset to come at 55 degrees (+ or – 5 degrees) Fahrenheit and go off at 65 degrees (+ or – 5 degrees). Larger steel units use a Fenwall thermostat, which is adjustable from 0 degrees Fahrenheit to 100 degrees.
If these units are being used in a freezing environment, the answer is yes. The exception to this is using Thrifty King units that meet the requirements for energy free usage.