This is a step you should have done in winterizing. What you should do is, open the low point drains (located in the skinny cabinet under the fridge) and then turn on your water pump and keep pumping until red antifreeze starts running out of the low point drains. Then run back inside and switch off the pump and close the low point drains. This works better with two people as you can have one person outside watching the water coming out of the low point drains and then yelling to the person in the trailer to close the drains when the antifreeze starts coming out. If you didn't do this step, you still have water in the lines that are leading to the low point drains.
2010 Jayco JayFeather 213 EXP
2016 Ford F-150, 4x4, 3.5L ECOBOOST, MaxTow, Supercrew, 6.5FT, 3.55 axle