Not a problem. Since a diaphragm mechanism is dry, any ice formation will be on the outside of the reg. The spring end that is nominally exposed to water is at the opposite end of the regulator from the valve, where all the adiabatic cooling occurs.
And unlike virtually all other second stage designs, the Mares design uses a bypass tube to take gas from the valve to the mouthpiece, while the lever mechanism does not have gas flowing through it. All the adiabatic cooling occurs at the valve, with the cold carried down stream.
Here's an old NEDU -1°C picture that shows the hose connection and bypass tube completely covered in ice, while the body of the regulator was clear. That means the lever mechanism won't freeze up. All other brands carry the cold gas downstream from the valve right through the lever mechanism. Mares is unique.
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And unlike virtually all other second stage designs, the Mares design uses a bypass tube to take gas from the valve to the mouthpiece, while the lever mechanism does not have gas flowing through it. All the adiabatic cooling occurs at the valve, with the cold carried down stream.
Here's an old NEDU -1°C picture that shows the hose connection and bypass tube completely covered in ice, while the body of the regulator was clear. That means the lever mechanism won't freeze up. All other brands carry the cold gas downstream from the valve right through the lever mechanism. Mares is unique.
versus