The T4398 Series Performance Thermostat:
Line Voltage Dual Diaphragm temperature Control Heat Wall Thermostat
The vast majority of line-voltage thermostats employ a bimetallic element to sense and control the heaters. This design works on the principle that different metals expand and contract at different rates as the heat and cool. These thermostats are cheap to make, but they tend to be inaccurate and to allow a very broad deadband. The deadband is the temperature range between when the thermostat turns the heaters on and when it turns them off. An old bimetallic thermostat could easily allow for an eight degree deadband or greater. That means that, if you set the thermostat for 68 degrees, it would not turn the heaters on until the temperature dropped to 64 degrees, and it would not turn the heaters off until the temperature reached 72 degrees. If you have baseboard heaters and you experience large changes in temperature while keeping a constant thermostat setting, th (more…)

The T4398 Series Performance Thermostat:
Line Voltage Dual Diaphragm temperature Control Heat Wall Thermostat
The vast majority of line-voltage thermostats employ a bimetallic element to sense and control the heaters. This design works on the principle that different metals expand and contract at different rates as the heat and cool. These thermostats are cheap to make, but they tend to be inaccurate and to allow a very broad deadband. The deadband is the temperature range between (more…)