Recirculator works to prevent frozen pipes

Thanks to this board, I found out about hot water recirculators.

Since I have now survived one winter, I want to report back that a recirculator seems to be a good last ditch solution for pipes susceptible to freezing. I have a bathroom addition on my house made of concrete block. The pipes supplying it are inaccessible without major demo and will freeze in cold weather. In past winters, I had to leave a faucet dripping on the coldest nights to prevent freezing (which sometimes wasn't enough). This fall I installed a Grundfos Comfort Series recirculator and it worked great all winter. I wasn't interested in the "instant" hot feature, but just the fact that it drew hot water and fed it back through the cold which prevented either pipe from freezing. Am now going to turn the recirculator off for the summer, but wanted to pass along my success in case anyone else faces a similar problem.