My insurance company recently sent me a letter asking us to upgrade our electric service size to a 100 amp service. They state in the letter that a previous owner reported that the house has a 60 amp service. I called in a friend who knows a few things about electricity and he says the service wire coming into the panel is a 60 amp wire but the breaker and the electric panel are both rated at 100 amps. It seems to me that because I have a 100 amp beaker and panel I have a 100 amp service.  So what do I tell the insurance company?

Unfortunately, you have a few problems. The first is with the safety of your system. For instance, because you have a main breaker and electric panel that are rated to carry 100 amps, your branch circuits could readily draw 100 amps through the branch circuit wires in your system. The problem is simply that your service wire supplying the main panel can only safely carry 60 amps. If more than 60 amps are drawn through this main service wire it could overheat and fail, causing a fire in the 60 amp wire feeding your panel. As well, if your service wire runs inside the exterior wall of your house, an overheated service wire could ignite a fire in this wall.

The second problem you may encounter is with your insurance company. They are correct to say that this is a 60 amp service. The reason is simply this. The size of your electrical service is determined by the size of the breaker or the service wire, whichever is smaller. Therefore, you have a 60 amp electrical service.

You could easily reduce the risk of fire and improve the overall safety of your electrical system by having a qualified electrical contractor change your main breaker from 100 amps to 60 amps. This will likely bring your system into compliance with Electrical Code specifications. However, your insurance company may still want you to upgrade the size of your service to 100 amps. This can only be accomplished by replacing your 60 amp service wire from the hydro pole to your distribution panel. Also, because the new 100 amp service wire has a bigger wire diameter, you will likely require a bigger service mast and conduit. Unfortunately, none of this work is the responsibility or domain of the public utility service provider. Therefore, you will need to hire a qualified electrical contractor to make these changes to your service if the insurance company requires this upgrade.