Safe propane tank freezing situations
Propane liquid becomes a gas at -44°F, which is a very low temperature. High air humidity can cause condensation to form on the tank exterior. Because the tank is particularly cold given the low temperature of liquid propane, this condensation can freeze.
Similarly, very cold outside temperatures can lead to a decrease in pressure inside the tank. Remember, propane expands and decreases in volume with temperature. Lower pressure leads to a fall in the propane temperature of propane inside the tank and reduces the propane flow. This decrease may cause the propane tank to freeze inside.
Propane tank regulator frost under normal circumstances
Propane regulators modify the pressure between the level at which propane exists the propane tank and the level that is required to fuel appliances. Frost can form on a regulator if there is a high level of humidity where the regulator is situated when propane passes through it. Since propane boils at a particularly cold temperature, the regulating process can produce condensation and frost appearing on a regulator in hot or humid climates is entirely normal.
Propane tank regulator freezing because of liquid propane flow
When liquid propane (as opposed to propane in its vapor form) enters a regulator suddenly and passes through it, the regulator may freeze entirely (as opposed to frost appearing on a regulator). This might happen if the propane tank is over filled. While this is very rare, it explains why propane tanks are only filled to 80% capacity.
The danger of having liquid propane flow through a regulator is that appliances are not designed to work with liquid propane but with propane in its gas form. This will damage your propane appliances and poses a safety threat. If you suspect this is happening, open the bleeder valve and check whether there is frost on the regulator. If so, close the service valve and call your propane company to have a qualified service technician come and examine at the situation.
Choosing a reliable propane company with a responsive safety number
This shows how important it is to be able to call a reliable propane company with a responsive and available safety emergency number that is open 24/7/365. Propane users may not know the difference between a situation where frost appears but that poses no safety threat and one where frost implies malfunctioning appliances.
If the former, your propane company’s services should be available and able to explain that there is nothing to worry about; if the latter, you will want to be able to have a qualified service technician come to your home to fix the situation.