Temperature in Arkansas recently dropped to about zero degree F, freezingly cold. My HydroTemp unit (built in 2005 and worked mostly fine over the last 15 years) quitted working and the low pressure light came on. 1. Water flow issue I can feel the water frozen inside the coils next to the booster pump. The water reservoir has ice in it and we added hot water to melt the ice. It seems that the antifreeze in the system is probably too low to be effective. I have a few questions. Will the water coils burst and leak water? If not, can I just warm up the coil and loop pipes to solve the "too little water flow" issue and thus the low pressure lockout? Are there any efficient ways to warm up the coils/pipes? Hope to get some discussions from the forum participants and see if anyone has similar issues. 2. Not a freon isssue, or themostat, or dirty filter, or evaporator coil dirty -- we checked all of those. We did add 1lb freon, then up to 2 lb to the system and it did not solve the problem. Thanks a lot in advance!