How to Install Thermostatic Radiator Valves

In this how-to video on energy efficiency, This Old House plumbing and heating expert Richard Trethewey shows how to create mini-zones in your heating system by installing a thermostatic radiator valve to control the heat output of a single radiator. Steps:
1. Drain water from radiator.
2. Use pipe wrenches to disconnect old valve from radiator.
3. Remove spud using a spud wrench and pipe wrench.
4. Apply thread sealant to new spud, then wrap single-strand wicking around the spud threads.
5. Use a spud wrench and pipe wrench to install the new spud.
6. Apply pipe dope and single-strand wicking to the threads of the existing pipe.
7. Install the new thermostatic radiator valve and tighten with a pipe wrench.
8. Apply pipe sealant to face of spud.
9. Tighten connection between spud and new valve using a pipe wrench.
10. Drill hole in radiator cover.
11. Feed wire through hole, then screw sensor to side of radiator cover.
12. Connect the sensor’s wire to the valve.
13. Slide radiator cover into place.