QUESTION: How often should gutters be cleaned?ANSWER: I'd recommend twice a year: in the spring and again in the fall. But that doesn't mean you shouldn't keep tabs on your gutters all year long. During the spring cleaning, check for any damage that might have been caused in winter by snow and accumulation of ice in the gutters.Fall is a good time to remove leaves and other debris that started to fill the gutters as soon as the trees began shedding their leaves. Evergreens tend to shed their needles at different times, though, so if your house is surrounded by pine, spruce and similar trees, add a third gutter cleaning to your schedule.If there's a downpour and rainwater pours over the edges of a gutter, that's a clear sign the gutter is blocked. Another sign: If it hasn't rained for a couple of days and you can still hear water dripping along the downspout, it means water is making its way slowly past a blockage.When gutters are installed properly, they work properly. But even when the installation is correct, the weight of water and ice can knock them out of alignment - which can mean gutters that no longer slope properly and don't carry water directly to the downspouts. Get the necessary adjustments made - by the roofer who installed the gutters, if possible.

QUESTION: What is the proper way to run central air conditioning? Should I leave it on all summer, adjusting the temperature as needed, or turn it on in the morning and off at night?ANSWER: Continuous operation of a central air-conditioning system can be efficient - it's all the starts and stops that require additional energy. Eliminate those and the system will run at peak efficiency. Still, you don't want to waste energy by running the system at a constant temperature if you don't have to.The answer is a programmable thermostat, which can be set for the times you want the house to be warmer or cooler. You can program the thermostat to raise the temperature when you leave the house. Then, two hours or so before you return, the thermostat will begin lowering the temperature to, say, 74 degrees from 78. If you shut off the system when you leave and restart it when you return, it will take a longer time and much more energy to overcome the heat that has built up.

QUESTIONS: A piece of wood trim just below the edge of my porch roof is rotted. Someone told me that it was probably a 2-inch-by-6-inch board. When I went to replace it, I discovered that the new board was too thin and too narrow. What did I do wrong?ANSWER: That piece of wood trim is called a fascia board; it's the board to which a gutter is typically attached.If a 2-by-6 couldn't be used to replace the fascia, it's likely your house predates standard building codes. In the old days, a 2-inch-by-6-inch board was 2 inches thick by 6 inches wide; today, a 2-by-6 is actually 1½-by-5½ inches. The lesson here: Always measure the piece you're replacing.You can overcome the half-inch difference by having a lumberyard cut down a wider, thicker board to a true 2-by-6 using a table saw and a thickness planer. A carpenter can do the same thing and make the repair quickly.I've made such repairs without a table saw or thickness planer. To compensate for the difference in thickness of the old and new boards, I cut pieces of lumber to fill the gap. The pieces were only a half-inch thick, and if I had tried to drive a nail through them, I would have split them. Instead, I predrilled several holes in each piece and then nailed the pieces through two of those holes to the rafters. Then I marked the locations of the other holes on the new fascia board and predrilled those, so the nails I hammered into the fascia did not split the pieces I'd nailed to the rafters.Send questions to The Philadelphia Inquirer, Box 8263, 400 N. Broad St., Philadelphia, PA 19101 or e-mail aheavens@phillynews.com.