Interestingly heat spreads better than cold (I’m not an entirely reliable source for this so take it with a big grain of salt) but essentially since hot things are more energetic they have a tendency to spread but since cold things are more static, cooling is more difficult. Also radiators use blackbody radiation to emit heat via light the same way metal heats up when hot whereas there’s no cold equivalent to this.
It’s more because of the temperature differential. The more difference between the temperature of two objects, the faster they change temperature. A radiator with 50 degree water is ~30 degrees warmer than the room (or 80+ degrees for a steam rad), while cold water is going to be 10-15 degrees cooler than the room. Any colder and you need to use not-water so it doesn’t freeze. Condensation or frost is also a big concern to avoid property damage.
Interestingly heat spreads better than cold (I’m not an entirely reliable source for this so take it with a big grain of salt) but essentially since hot things are more energetic they have a tendency to spread but since cold things are more static, cooling is more difficult. Also radiators use blackbody radiation to emit heat via light the same way metal heats up when hot whereas there’s no cold equivalent to this.
It’s more because of the temperature differential. The more difference between the temperature of two objects, the faster they change temperature. A radiator with 50 degree water is ~30 degrees warmer than the room (or 80+ degrees for a steam rad), while cold water is going to be 10-15 degrees cooler than the room. Any colder and you need to use not-water so it doesn’t freeze. Condensation or frost is also a big concern to avoid property damage.