James Dulley, Published April 01 2011
Dulley: A whole-house system best for blocking surges
Dear Sandi: People often think of only electronic gadgets such as computers, game consoles and audio/visual items as being at risk from electrical surges. Actually, nearly every electric item in a house today has some sort of sensitive electronics that can be damaged by a surge. These include ranges, dishwashers, air conditioners, fans, etc.
A very common source of an electrical surge is a thunderstorm. The voltage and current spikes from a lightning strike are enormous. If your house and wiring experience a direct or very nearby hit by lightning, even a good surge suppressor likely will not be able to protect all electronic items.
When a storm is forecast and you begin to hear thunder in the distance, unplug as many of your electronic devices as possible. Just switching them off may not be adequate protection. A huge voltage surge can arc across an open switch and still fry the electronic components.
It often is repeated by smaller electrical surges, which damage electronic equipment over time. These can be generated from the switching on and off of inductive equipment (usually electric motors) in nearby businesses. Some of these smaller surges can even be generated by your own vacuum cleaner, refrigerator compressor or clothes washer motors in your house wiring.
These smaller surges can slowly break down wire insulation or some electronic components over time. Eventually a wire may short out or the electronic component begins to malfunction and the appliance fails.
There are several types of whole-house surge suppressors available. Some mount on the circuit breaker panel indoors or are built into a circuit breaker. Others are designed to mount underneath an electric meter. Many electric utility companies sell and install the electric-meter-style units for you. The circuit breaker panel models are not difficult to install, but hire an electrician to do it.
There are differences in the protection provided by various surge suppressors. A common design uses metal oxide varistors to absorb the electricity surge and dissipate it before it flows through the house wiring.
A physically larger MOV can absorb a larger surge. The basic specifications to compare surge suppressors are the maximum surge current (amperes) and the total energy dissipation (joules) it can handle. A higher number for both is better.
Even though the surge suppressor protected your electronics, a large surge many burn out the MOV. Many models have a light on them to indicate if it is still functional or not. Check it regularly and especially after a thunderstorm.
The following companies offer efficient surge suppressors: Eaton, (800) 386-1911, www.eaton.com; Emerson Network Power, (800) 288-6169, www.emersonnetworkpower.com; Intermatic, (800) 391-4555, www.intermatic.coma>; and Meter-Treater, (800) 638-3788, www.metertreater.com.
Dear Jim: I like to use my brick fireplace, but I don’t often because the room get smoky. The fireplace opening is pretty big – 36 by 36 inches. What can I do to reduce the smoking? – Frank K.
Dear Frank: Have the chimney cleaned and inspected first to make sure nothing is blocking the smoke path. Tiles can break loose and fall together partially blocking it. A chimney fire may have caused creosote to puff up.
It sounds as though the fireplace opening dimensions may not be correct. If the height of the opening is too high above the burning logs, the draft can be insufficient. Try using a grate to raise the logs from the floor or put a steel plate across the top to reduce the height/width ratio of the opening.
Send inquiries to James Dulley, The Forum of Fargo-Moorhead, 6906 Royalgreen Drive, Cincinnati, OH 45244, or visit www.dulley.com