room Stats

[safc]

Can anyone tell me the difference between a changeover roomstat and a on/off roomstat ?

 

[doitmyself]

Can anyone tell me the difference between a changeover roomstat and a on/off roomstat ?

An on/off stat has a two terminals connected by a single throw switch, which is either open (up to temperature)or closed (below temperature).

A changeover stat has a double throw switch, like a two-way light switch, so it's either connected A-B or A-C, depending on whether the temperature is below or above the stat setting. It's used when you have heating and cooling systems.