Q: Is it worthwhile to add a dehumidifier to an existing heating system? If so, about how much would it cost? I have a gas-fired furnace and central air.

Our house in the winter is dry, and I shut down the basement dehumidifier from November to April because it is in unnecessary and expensive to run, although I’ve never broken down the electric bill to determine costs. Our gas furnace has a humidifier that adds moisture once the relative humidity falls below 30 percent (the 30 percent to 50 percent range is considered comfortable). By keeping the humidity above 30 percent, you can normally turn down your thermostat a few degrees. With higher humidity, your heated air will feel warmer.

Yet, adding a dehumidifier to the HVAC system as well is not a bad idea, since the more moisture you can remove from the air, the less clammy you feel. There are other reasons – mold, mildew – for keeping the relative humidity in the target range. But comfort is probably the best one for your purposes.

The square footage of your house would determine the size, and thus the cost, of the dehumidifier. I’ve seen prices starting at $1,000, plus installation. A professional would first determine whether your present HVAC system would accommodate a dehumidifier and size it properly. On site inspection works every time.

Dust those ceiling tiles

Q: Almost 30 years ago, we installed ceiling tiles in our bedroom. They’re glued to the ceiling, not hanging on grids. Although they’ve held up well, they drop a lot of tiny particles, causing quite a vicious dust problem.

I contacted the manufacturer, which advised us to vacuum the ceiling. We don’t have a vacuum with a hose long enough, and can’t imagine holding it up the entire time – those things are heavy! We had asked if there was some substance we could coat the tiles with that would seal them, but Armstrong said just vacuum them.

We’re willing to give that a try once, but would like to be able “lock in” our results to avoid ever having to do it again. Ceilings get dirty and dusty, whether they are plaster, drywall, metal or tiles. As much of a stretch as it is for you and your vacuum cleaner, whatever the manufacturer suggests for cleaning the tiles, one follows it. Painting or coating the tile might create residue that is even more unpleasant than dust.

Rusty radiator

Q: My sister has a full bathroom that is quite small. The baseboard radiator is situated behind and alongside the toilet. The radiator keeps developing rust. Her husband sanded and painted it with Rustoleum paint but it kept returning. They eventually had it replaced with a new one. It is starting to rust again. A friend recommended painting it with automobile paint. Would this remedy the problem?

When condensation forms on the metal surface, rust appears. Preventing it is a constant job, not a one-time thing. You simply need to keep after it, as you must do with most things.

Philadelphia Inquirer

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