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posted: 12/2/2012 5:27 AM

AC units in windows need winter protection

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Q. Should I cover my window air conditioner? I have no one to help and wonder if I can do this myself. I'm a senior citizen. What type of cover should I buy, and how do I measure for it?

A. Yes, you should cover your window air conditioner for the winter, and you may be able to install a cover yourself, depending on the accessibility of the unit and your physical condition.

Measure the width, height and depth of the unit and take these measurements to the store. The clerks should direct you to the right size. You can get covers at hardware stores, home supply stores such as Home Depot and Lowe's, or online at, etc. Some covers are insulated, which may be worth considering if you live in a cold climate.

Air conditioners installed in double-hung windows present a special problem. The lower sash is raised, which leaves several gaps for cold air to enter the house unless the gaps have been thoroughly weatherstripped. An electrician, contractor or handyperson can verify this for you and install the cover if necessary.

A better approach is to remove the unit and store it for the winter, but this is not always practical.

Q. We have an older home in Glen Ellyn and we have been told by the folks who recently installed an air conditioner unit in our attic that we need to put in more insulation and ventilation.

How do we find someone (a contractor?) to help us with these projects? We don't know where to start.

A. Your best approach is to call a contractor certified by your local power company or energy office to perform energy audits. He or she also may be certified to perform the work.

Q. Our back basement wall is cracked at the mortar joint, two courses down from the cap. What method do you recommend to rectify this situation? It is stable and hasn't moved, but we would like to have it repaired.

A. Block foundations are prone to these horizontal cracks a few courses below grade. These cracks are caused by frost pressure pushing in the walls.

The first thing that needs to be done is to correct the grade deficiencies that are responsible for the problem. The grade should slope away from the foundation at a gentle rate and be covered with grass or a thick ground cover, or, if your house has no gutters, masonry units flush with the grade at the roof's drip line to prevent roof water from eroding a trench in the soil.

A masonry or general contractor should be able to correct the problem by digging down a couple of feet to relieve the pressure on the wall and see if it comes back by itself; sometimes it will once the pressure is removed. This should be followed by grade repairs.

An alternative is to have foundation specialists look at it and suggest a solution. There are several: plates installed against the crack and tied to rods and "dead men" buried in the ground some distance from the wall; fiberglass strips glued to the wall to stabilize it, etc. These systems may not straighten the wall, but they do work, and are likely to be expensive.

Q. We have a natural gas fireplace covered by glass and an exterior metal grate. One of our children leaned too close to it one day, and it melted her windbreaker to the grate. (She thankfully moved once she began feeling very warm.) But now the melted windbreaker is stuck to the black grate. Do you have any suggestions for how we might remove it from the grate without damaging it? We tried Goo Gone after warming the grate, but that didn't seem to do it.

A. Scraping it off with a plastic tool may work, but it also may damage the finish on the grate. The tool to try is the SKrAPr, specially designed to remove foreign materials from glass cooktops. I also have used it to clean barbecue grills. You can see what it looks like and get it online at You also could try an oven cleaner or barbecue grill cleaner.

Q. My daughter recently had work done in her kitchen. I'm concerned, because the light switch on the wall gets very warm, and I don't think this is safe. Should I be concerned?

A. Yes, indeed! It's a potentially dangerous situation, and she should have a licensed electrician look at it as soon as possible.

Q. Next year we're having a log home built in western Kentucky and are considering the tankless, on-demand type of water heater. We're empty nesters who need lots of hot water only when we have company. The ranch-style house will have propane gas and three bathrooms, three to four bedrooms and a walkout basement (two bedrooms, one bath in basement).

Is the tankless, on-demand water heater more practical than keeping a tank full of hot water?

A. Tankless water heaters are popular in other countries and are becoming more so in the United States. They have some energy-saving advantages but also some drawbacks. Their main advantage is in saving energy, but the upfront cost is considerably higher.

Tankless heaters must be tailored to your individual situation. In your case, a unit that would satisfy your needs may not be sufficient to take care of the additional demand when you have company, unless it is understood that no two people can shower at the same time, or that showering cannot occur while the clothes washer is running, for instance.

If this is of concern, the solution is to choose a unit of greater capacity.

Q. I have saved three of your articles over the years that address bathroom fans. One warns about venting fans upward through the roof, which can result in condensation running back into the fan and staining the ceiling. Your solution was to run the duct horizontally in the attic to the nearest gable wall. You continued with what to use and how to do the job.

Another writer asked about venting the fan through a soffit. Your answer was not to do this because the soffit is an intake for outside air. Thus the discharge of a bath fan through a soffit is sucked back into the attic.

In the last article, you suggested that, because the party lived in a ranch house, they vent downward through the basement and outside through the band joist. The duct should be run in an inside wall so as not to disturb insulation.

We live in a ranch-style house. We have asked for two bids for redoing our first-floor bathroom. One company would vent the bathroom fan through one of the existing roof vents. The second contractor said that since we have a window in our bathroom, we would not need a fan/light (per city code). He then said that if we wanted one, he would vent it through the soffit.

Because we live in a ranch and because the outer wall will be open to the studs, could he vent it downward? We have a finished bathroom directly below the one to be rehabbed. Where is the band joist? The house is all brick. It's a long way from the bathroom to the gable end of the house, which is why we don't think venting that way is good.

A. It always amazes me that so many contractors are ignorant of the problems they can cause.

Venting the bathroom through one of the existing roof vents tells me that he plans on venting it through a gable vent. To do so means that the duct would be run up to the vent. This is the same as venting through a ridge vent or through the roof; condensation will run down and rust the fan and stain the ceiling. Since gable vents can be intakes as well as exhaust, depending on the wind direction, it also can bring the moisture back into the attic.

Having a window in the bathroom makes it unnecessary to have a fan, but will you open the window to get rid of the moisture? A fan on a timer, which allows you to select five to 30 minutes of operation, is ideal.

If the soffit is unvented, venting the bath fan through it is possible, but be aware that the moisture the fan exhausts can cause mold to form on the soffit board and stain it.

Running any duct through an outside wall should not be done because it will get cold, which would cause condensation. It also would reduce the insulation needed in the wall.

Since there is a bathroom below, the lower level may be finished, so it would not be practical to vent downward. That suggestion is for unfinished, open basements.

The band joists, also referred to as rim joists, are the joists that cap all floor joists and form the perimeter of each floor framing system. Depending on the age and construction of your house, you may not have band joists; the joists may be set in the masonry.

In your situation, regardless of the distance, it sounds as if the best way is to vent through the attic with a rigid, bell-end Schedule 20 pipe installed with a slight downward slant to the nearest gable, and covered with ample insulation. The bell end must face the fan and terminate through the wall with a hooded jack equipped with a flap.

Stay away from jacks with several louvers; they are prone to break or get stuck in the open position. Some jacks also have a rodent cover, but such covers must be checked frequently and cleaned, as they will clog with lint quickly.

Perhaps you should consider talking to a more knowledgeable contractor.

Comment from a reader: "There is an easy fix to foul hot water smell! We had exactly the same problem while living in Connecticut. Our well had high mineral content, including iron. Our electric water heater worked fine until energy conservation came along and I turned the temperature down to about 115 degrees at the tap. A short time later, we had the rotten egg smell while showering.

"No one had an answer. I finally decided that the lower temperature was causing bacteria to grow in the tank, releasing hydrogen sulfide. I turned up the temperature a couple of degrees at a time, every couple of days, until one day the problem disappeared 100 percent. As I recall, the magic killing temperature for our bacteria was 120 to 122 degrees."

Note: That's a solution worth trying if the heater's temperature is that low. But this foul smell also happens at higher temperatures, and the sacrificial anode is a common source of it.

Some plumbing codes require the water temperature to be set at 140 degrees Fahrenheit to prevent bacteria growth, but to prevent scalding, they also require -- at a high cost -- a temperature reducer to bring the temperature back to 120 degrees. This is a contradiction to the earlier recommendation to lower the temperature to 120 degrees to save the water heater and extend its life, since calcification, which shortens the heater's life, sets in at 140 degrees.

Thank you for your feedback; it may be helpful to some people who have lowered the heater's temperature below safe levels.

• Henri de Marne was a remodeling contractor in Washington, D.C., for many years, and is now a consultant. Write to him in care of the Daily Herald, P.O. Box 280, Arlington Heights, IL 60006, or via email at

2012, United Feature Syndicate Inc.

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