My folks' vacation house has two-zone gas hot-water baseboard heat; one of the zones covers the whole upstairs - three bedrooms and two bathrooms. This weekend, they noticed that one of the bedrooms is getting really warm, and the others barely comfortable. Also, the heat doesn't seem to ever shut off, even though the temperature at the thermostat is above the set temperature.
Does anyone have any ideas or suggestions? Dad is planning to call for service but it'd be great to have some idea of what the problem could be.