It's that time of year where lights fill neighborhoods; flashing, flickering and glowing everywhere. It's beautiful. Ironically, Christmas lights can reveal electrical problems with your home, or they can create them. So far this season, we've answered two service calls related to Christmas lights.
The first one came in with this description: Half of the lights and receptacles were no longer working and the homeowner could not find the cause. The cause? The cause was a couple dozen interior styled extension cords plugged together and lying on the ground outside. The cords were exposed to water every time it rained. They were plugged into an exterior receptacle that was GFI projected. It tripped early on and continued to trip every time it was reset.
Exterior lights need to be on GFI protected circuits, but the cords that connect to the strings of light should also be rated for exterior use. Where the male and female cord ends plug together should also be weatherproof.
The second call had this description: All of the lights in the house do not work any longer. The cause? More Christmas lights than the circuitry could handle. This was an older home with an exterior panel. The homeowner had so many lights plugged in that it was blowing his 30 amp fuse. Finally, it melted his fuse base. The fuse fell out and all of his lights that were on the same fuse went out
The solution was to pull the old fuse box off the wall and replace it with a small sub-panel. A breaker replaced the fuse and the breaker size was reduced to the correct size to avoid creating a fire hazard. The former circuit was a 30 amp single phase circuit. It was 100% too big. The new circuit was a 15 amp circuit. It is no longer safe to put the Christmas lights on that circuit. To make sure the homeowner didn't try, we removed the exterior receptacle that was non-weatherproof.
Christmas lights are beautiful, and they do inspire a warm fuzzy feeling this time of year. It's important to make sure your electrical service is capable of handling the extra load. Also, make sure any exterior wiring or lights are appropriate for a wet environment. That will mean they are controlled by a GFI circuit and have weatherproof cords and junctions.
On a side note, emergency electrical service calls are very expensive. Save yourself the expense and the aggravation by doing your decorating safetly.