Replacing Hot Water Radiator Valve

MRC

Good Morning Forum,

Have a Customer who has an unoccupied room above her garage. Her home was built in 1929. It is heated with hot water. During the fall of 2013 she turned off the radiator supply valve, reasoning that this would save her money, not heating an unoccupied room. St. Louis got some really cold temps (thanks to the infamous polar vortex) during the winter of 2013/14. This Fall she had her boiler cleaned and checked by another company. The tech was bleeding the rads and when he opened the valve to this particular rad he found that the freezing temps last year caused an elbow in the return line to split. What a mess!
Techs from the company I work for replaced the 1" elbow. When they attempted to turn the valve back on the stem broke.
My question(s) are these...
1) Is this valve repairable? can I get a new stem for something this old...1929? Or...
2) Should I replace the entire valve with the same type manual shut off valve? Or...
3) Would installing a Thermostatic Radiator Valve be a better option? She could keep the temp in this (as of now) unoccupied room lower than the rest of the home.

Thanks, Mike

Ironman

Repairable? Doubtful.
Replaceable? Yes, but you'll have to remove the old spud.
TRV? Possible, but may be not advisable due to the possibility of freezing again. If it's set too low, freezing may occur again because enough heat migrates upstairs from below to keep the valve closed when the piping could be exposed to freezing. If this happens, you'll be liable for the damages because you modified it.