Anonymous wrote:73 is really hot for sleeping!

A humidifier will make a room feel warmer too. No wonder she's waking up sweaty.

+1. A humidifier will make the room feel hotter & stuffier. Turn off the humidifier, close the vents, and open the door. A fan (even a table top fan) will help.

OP, the problem is very simple. The small room has better heat retention/insulation compared to other rooms due to its singular window (less heat dissipation) and its size/volume. So every time the heater runs, the room is getting hotter than the other two rooms. Over time, the heat built up to intolerable level.
The solution is to restrict the heat intake in the room to a certain level by adjusting the vent opening (trial and error). Same thing with the humidifier. Don't turn it up too high. Consider getting a fan to distribute heating evenly in the room.

What is the temp range you guys running in the house (daytime, nighttime)? We are in montgomery county, so it is winter now, and we work from home.

I run cold and agree 74 degrees 24/7 is insane!

For the summer you can buy a register booster - it’s a fan built into a register cover that will push more air into that space. We have our house fan set to rise. 15 min of every hour. This takes care of hot/cold spots.

73-74 is at the thermostat. Closed door small room with open vent would be around 78. A humidifier makes the room hot and humid. Without the humidifier, it's hot and dry.

Keep the vent opening at the minimum and put in a small fan. That's the work around.

73 is really hot for sleeping!

A humidifier will make a room feel warmer too. No wonder she's waking up sweaty.