I was at a customer’s house in Greenwich, CT last week when he was complaining that his furnace was not getting power. I started at the electrical panel and tested each circuit breaker. Each breaker had the right voltage, so I know the problem was not outside the house, and not in the panel. He had some work done in his basement recently and was concerned that a worker had cut a power cable by accident. The problem was somewhere within the house.
The next step was to check the most obvious causes. In most cases, the National Electric Code (NEC) requires two shut off switches for a furnace. One switch is on the unit so a technician can turn it off when servicing the equipment. The other switch is somewhere close to the living area, typically on the top of the stairs going to the basement. What had happened was someone must have accidentally flipped that switch off while walking past it. Once I flipped the switch, the furnace worked perfectly.
This situation happens all the time. It usually involves someone who just moved into the house, and accidentally flips the furnace switch. Sometimes it is a relative who was trying to find the light for the basement, or a mover carrying a large box, or a maid. The remedy for this situation is a plastic switch cover that costs only a few dollars at hardware or home centers. It is worth the money many times over to avoid losing heat in your home.
So, next time the furnace in Greenwich, CT does not get electricity, check the two furnace switches, which usually have a red switch plate.