The electro-mechanical thermostat dates from 1883. If you have a manual thermostat in your New Jersey home that Warren S. Johnson, its inventor, would recognize, consider replacing it with a 21st-century programmable thermostat. A programmable model is safer and will save money, time, and energy.


When your furnace or central air conditioner runs less often, you lower your energy bill. Easily decrease furnace fuel use by removing the old thermostat and installing a programmable model that drops empty house and overnight temperatures by several degrees. The low cost of the thermostat is earned back from just a few weeks’ fuel savings.


If you constantly adjust your manual thermostat to make your home comfortable, a programmable thermostat will save time.

You need to reset a manual thermostat each time you want to increase energy efficiency. Unlike a manual thermostat, a programmable thermostat requires one programming session for the four daily times: morning, empty house, return, and overnight.

  • For your empty house, set a lower heating threshold (the house cools off in winter) or a higher cooling threshold (the house heats up in summer)
  • Program comfort temperatures for your expected return time
  • When going to sleep, lock in the lower heating or higher cooling thresholds again


Program the thermostat for setback temperatures a few degrees below your comfort when you are out or asleep. This will improve your energy efficiency because the furnace is not wasting fuel on heating an empty house. Similarly, save electricity by reducing your A/C use.

But My Old Thermostat Still Works!

The old dial electro-mechanical thermostat has a small glass ampoule with mercury in it. Mercury—liquid at room temperature and easily dispersed—is dangerous. Getting the old thermostat out and replacing it—even if you simply get a digital thermostat—is a safe first move. Better, replace that dial thermostat with a programmable or WiFi thermostat. Modern thermostats are far more accurate than older designs, which means your HVAC systems run more efficiently.

For more help in replacing a manual thermostat with a digital or programmable thermostat, contact us at Pipe Works Services.

company icon