Seat belts are good for people, flea and tick medication is good for pets, and surge suppression is good for buildings with electricity. Most everyone agrees. The question with surge protection is not whether it’s a good thing, but rather is it worth it? Is the cost of the protection worth the risk of damage, how many levels of protection are appropriate, and are you comfortable recommending an add-on that the customer hasn’t asked for?
Surges come in three varieties. The best known are surges caused by lightning strikes. These are by far the least common, and most damaging, of the three. Direct, or even nearby, lightning strikes are impossible to protect against with everyday panel or appliance surge protection. The surge is just too big for that much voltage to be shunted to ground. In order to be protected from lightning strikes a building must have a surge protector located before the service panel in combination with a lightning rod and a trip breaker that cuts power if the first two defenses fail.
Surges and spikes in current can be caused by your utility. Switching, transformer failure, downed lines are some of the sources of spikes and surges from utilities.
By far the most common source of surges and spikes comes from within a building. When appliances and equipment turn on and off they create small spikes in the current; for larger equipment causing a surge during a cycle is common, often occurring many times a day.
Probably as important as protecting appliances against catastrophic surges is the need to protect them against the day-in and day-out wear and tear to electronic devices that small surges cause. Think of waves eroding a beach. No single wave is terribly destructive, but together they wash away the shore.
Whole-house surge protectors will go a long way towards intercepting surges from exterior causes, and can help mitigate some of those internally generated surges and spikes. A second tier of surge protection is recommended for appliances with solid state components (which is just about everything these days). The second tier protects individual components from whatever is happening to the current within the structure; whether it’s a surge strip for your computer or any of the surge protection add-ons for appliances that draw more current.
All this is a long-winded way of saying that, yes, surge protection at any level is well worth offering to your customers, whether it’s protection for a whole house, HVAC equipment or a home entertainment system. The decision about value vs. risk is the end users, but the responsibility to offer it to them is the contractor’s.