I have to use an electric dog water bowl for watering in my coop this time of year.That does allow for the wattles to get wet unfortunately. When temps get down below 15 F I will usually turn on a heat lamp just to keep the temps a little warmer than that. I do provide good ventilation overhead to help remove humidity.
Rooster waddles swollen and purple. Please help! - Page 2
This time of year it is so important to count the chickens in case one doesn't make it in to roost for the night. Locking them inside the coop at night doesn't always prevent it from happening, but lessens the chances. You may want to get some Vetericyn spray for his wattles, or use weak betadine on them. Procaine Penicillin G is found in many feed stores (it is refrigerated, there are several brands and shake it well.) Get some 3 cc syringes, some 20 gauge short needles. Give 1/4 ml/cc into the breast muscle 1/4 inch deep, alternating sides for 4 days in a row.
I use chicken nipple in the bottom of a 2 gal. bucket with a birdbath deicer in the bottom to keep it from freezing.