The Rival slow cooker temperature settings are low, high and warm. Only two of the temperatures, low and high, are actually intended for cooking, however. The warm setting instead keeps cooked food at a proper serving temperature.
The low temperature setting is best for those owners who want to begin cooking something in the morning or at night and then leave it for several hours while they go to work or sleep. The high setting cooks food at roughly twice the rate as the low setting.
Any time frozen meats are used in a recipe, however, the cooking time should be increased. Approximately a cup of water should be added to the cooker with the frozen meat as well to encourage even cooking. For the "low" setting, at least four hours of cook time should be added when using frozen meat. At least two hours should be added to the cook time when cooking on the high setting. Depending on the cut and thickness of the meat, it may be necessary to add even more cooking time. Once food is cooked, it can be kept warm by switching the setting to warm until it's time for the food to be served.