If a regulator freezes, it will stop functioning correctly and you’ll likely experience low to no gas flow. There are two major factors that influence regulator freezing.
First, if liquid propane is able to flow through your regulator (typically caused by the liquid level of the propane being above the level of the regulator), the regulator will freeze. Freezing due to liquid propane in a regulator happens within a minute of use.
If you are using a 1 pound propane tank, this can be resolved by closing your valves and the propane tank, disconnecting the propane tank, and waiting for the regulator to thaw before reconnecting the regulator to the propane tank with the liquid level of the propane canister below the regulator (the regulator should be at a 45 degree angle towards the back of your griddle, with the bottom of the propane tank resting against the table or shelf your griddle is on).
If you are using a bulk (20 pound) propane tank and it is freezing because propane is flowing into your regulator, it could by a symptom that your tank is overfilled. If your propane tank has been overfilled, close the tank and your burners and discontinue use of that propane tank immediately and contact your propane company.
Second, if you are cooking while it is cold outside, the regulator can freeze if your propane tank gets too cold. Propane tanks function by allowing liquid propane to expand into gaseous propane, which your griddle burns. It takes heat for liquid propane to become a gas, and continued use of a griddle in cold temperatures can cause the propane tank to not be able to produce enough heat for liquid propane to evaporate into gas. When this happens, not enough propane is able to evaporate to fuel your griddle, and heat is taken from the regulator, which can cause it to frost over. If this occurs, close your propane tank and valves and wait for the regulator to defrost before continuing cooking.