We're having an intermittent issue with lights dimming in the entire house (or at least on different circuits at the same time). I do NOT notice any brightening of the lights, just dimming. The lights will flash from normal to slightly dim and back and forth usually for about 2 or 3 seconds then calm down for a while. I've been trying to pin point a particular appliance but when it happens nothing is running. Also, when our refrigerator compressor or clothes dryer starts up the lights dim briefly. I understand that this can be normal, however we have never noticed those particular appliances dimming the lights before. We'll have the dimming issue even when most everything is off in our house so I don't thing we are overloading. The grounds/neutrals are tight in the breaker box. I haven't tightened the main neutral from the utility as I don't have the right size hex bit yet.

Christmas lights/trees have recently gone up around the neighborhood and in our house. Can the extra load in the neighborhood cause problems from the utility company? Could a problem with our Christmas tree lights or Christmas lights on our house dim the entire house? I would think it would only effect the one circuit, or at most only one phase. Where should I look in the house and what are the troubleshooting steps? Should I call the utility company first?

Yes, contact the utility. If the dimming just started with all the Xmas lights in the neighborhood,then the transformer may be overloaded, or defective, or there is a loose connection in the utility system.

The loose connection may be in just your line from the utility.

The utility came out and discovered the neutral was loose in the meter box as a result of the ground settling beneath the box. This sounds like it was most likely our issue.

Thanks