It's been years...But I think I ran them both to open them up and the heat from the hot pipe helped to warm the cold pipe.
I think I let it trickle during the daytime.
If I had to do it again, I'd look into insulation sleeves. This was all in the upstairs bathroom so part of the pipe was behind a wall.
If your pipes are exposed...look into the sleeves.
Best advice..ask at Lowes or someplace like that.
Thanks....If it freezes it will be from the basement area where pipes are. One side of the building is exposed to the road. Though I’m still not sure it was here or the city. There were three breaks in my neighborhood last round...water line, gas line and sewer line in three different areas within a few blocks.