May 17, 2010

      Dear Ken: We have a townhome with a major dust problem. Should we have the ducts cleaned? Add an air cleaner? Replace the carpet or what? Bob
      Before you spend chunks of money on new systems, let's check the envelope you live in. Many times there isn't enough "makeup" air. That's the air that replaces what you exhaust outdoors through the bath and kitchen fans, fireplace, and dryer vent. That produces a negative air pressure inside, which is made up for by sucking air through unintended openings (we'll get to them later).
      Because of our obsession of saving energy at all costs, we sometimes don't have enough "holes" to the exterior. Have an HVAC contractor check the air sources, including the combustion air openings to the gas appliances. You may need more openings directly to the outside, additional ducting and maybe a filter or two.
      You have weep holes through all of your window frames. They are small (usually) square openings at the bottom corners of each exterior window casing. To mitigate the dust intrusion, insert a small piece of sponge into each hole. That allows water to drain out, while keeping the dust particles at bay. Also, check for a gap at the bottom of the siding where it meets the foundation. If there is one, spray a little insulating foam underneath, or, alternatively, chink some fiberglass insulation into the gap with a screwdriver.

     Dear Ken: Which are the best tankless water heaters? You mentioned them on the radio show, but I lost the list. Thanks, Shaunna
      The one you hear most about is Rinnai. It's a good, although pricey, on- demand water heater. Other brands include Rheem, Bosch, State, and Bradford White. Make sure that whichever brand you choose provides at least 7 gallons per minute throughput of hot water. That way, you can run at least two fixtures at a time.
      I've mentioned before that I'm not a big fan of these tankless systems. They are touchy and sometimes shut down for no apparent reason. Also, they are expensive to install-plan on spending around $3000 or so for an installation in an existing home. You can buy four or five regular water heaters for that chunk of change. Plus it may take 15 or 20 years to amortize the tankless expense-and only then will you actually start saving money. Bottom line: My preference is to stick with a traditional tank-type heater, wrapped with insulation.

     Dear Ken: I have some kitchen cabinets that need a deep cleaning and then recoating. What product do you recommend? Can I varnish them afterwards? Scott
      Try one of the citrus-based restorative products, Scott's Liquid Gold, or Olde English. These will both clean and condition the wood. For really tough-to-remove dirt and pollution, use the ultimate degreaser: mineral spirits. Open the windows and take frequent breaks from the fumes.
Once the cabinets are cleaned, you could put on a new top coat; usually, wood cabinets are finished with lacquer. You'll have to de-gloss the surfaces first, then apply several coats of spray-on lacquer (best left to a pro), or you could brush on several coats yourself.

      Dear Ken: My flagstone walkway is gradually turning black. How can I clean it? John
      These can be organic (tree drips, for example) or inorganic stains-like water settling between the sealer and the stone. Try power washing first with some detergent scrubed in with a stiff brush. If that doesn't help, you may have tree sap staining that can be removed with one of the many organic stain removers, available at the hardware store or home center.
If all else fails, as a last resort, you can scrub on some muriatic acid. This is a form of hydrochloric, and, as you remember from high school chemistry, it can be pretty toxic-and release poisonous chlorine fumes under certain conditions. So, follow the directions assiduously, and wear protection-especially safety goggles.