Comfort Line - Thermostats

This quarter our Questions and Answers segment discusses thermostats and how they can increase your comfort and save you money.

How exactly does a thermostat work?

A thermostat is a simple, normally off, electrical switch. When the temperature in the house gets above or below the thermostat setting, it completes a circuit, signaling your heating or air conditioning system to get going.

If I turn my thermostat way up or way down, does it make the house heat up or cool down faster?

No. Thermostats are designed only to turn your heating or air conditioning on or off. The speed at which the house heats up or cools down depends solely on the size and insulation level of your home and the capacity of your heating or air conditioning system.

Since thermostats are electrical devices, are they dangerous?

No. Almost all residential and commercial thermostats are low voltage (24 volts). This is not enough electricity to harm you in any way.

I have an old thermostat. Should I consider replacing it?

If you are happy with the way your old thermostat works, there is no reason to replace it. However, earlier generations of thermostats used a mercury switch to turn your heating or air conditioning system on or off. Newer models are digital micro switches and therefore somewhat more accurate and reliable.

How do setback thermostats work?

Setback thermostats are programmable and can be used to raise or lower the temperature in your home at various times during the day. The most common type of setback thermostat contains four time and temperature settings for each day. For example, you can set back your heating or air conditioning while you are away at work and bring it back on before you come home. You can also adjust the temperature in your home at night when you are sleeping.

How much energy can I save with a setback thermostat?

This depends on the configuration of your heating or air conditioning system and how religiously you use the setback feature of your thermostat. In general, savings in the 10% range are most common.

What is the optimum temperature setback for best savings?

A good rule of thumb is 5° F. This number can vary depending upon how extreme the outdoor temperature is and the length of time that the system will be set back.

I have a system with an indoor/outdoor setback control. Should I also have a programmable setback thermostat?

In general, if you have an indoor/ outdoor setback control, you should not use a setback thermostat. Indoor/outdoor setback controls adjust the temperature of the water in the boiler depending on the outdoor temperature. This improves comfort and generates significant energy savings. However, with an indoor/outdoor setback control, if the temperature in the house is set back, it can take a long time for the temperature to recover. Therefore, it is generally best to use the setback feature contained in most indoor/outdoor setback controls, rather than a separate setback thermostat.