Vacuum static furnace filters before washing

Q. Some time ago, you discussed the difference between static filters and paper filters for efficient furnaces.

I purchased my furnace about three years ago and have the static filters. I find them very bulky and hard to clean every month, especially in the Chicago-area winters.

Once I tried putting them in the dishwasher, but was advised not to do that because they were stainless steel. Currently I am soaking them in the laundry tub with hot soapy water.

I let them soak for about two hours, rinse, and let air dry. This takes several hours, then I reinstall them. In the meantime, the house gets pretty cold.

There is also still a film of dirt on them that can be wiped off with your finger. It would be impossible to wipe the filter completely off. Do you know of a product or method of cleaning them that would eliminate this film?

A. I am not sure whether what I have to offer will solve your problem entirely, but if you do not vacuum your filter first, wetting or soaking it will not remove all accumulated dirt; it will cause some clumping that will be difficult to remove.

The most important first step in cleaning electrostatic air filters is to vacuum them thoroughly. Most filters will have an arrow on their sides showing the direction of the airflow; the arrowhead must point toward the furnace's side, the exit side of the airflow.

Vacuum them on the intake side, the one away from the furnace's fan, at the tail of the arrow, where the dirt has been trapped. Do so very thoroughly for several minutes.

There are several ways to clean these filters, and here are a couple of them:

Follow the vacuuming by spraying the filter, preferably outdoors if possible or over a sink or in a bathtub. Spray from the furnace's side, the side at the tip of the arrow, so as not to drive dirt into the filter, but push it out.

If the filter is unusually dirty, spray it with a mixture of dishwasher liquid and as hot a water as you can get until it is thoroughly soaked. Do so from the tail of the arrowhead side. Let the filter sit for five to 10 minutes to give the soap a chance to saturate all the accumulated dirt.

Thoroughly rinse with your garden hose set on the "shower setting" from the furnace's side of the filter, the one with the arrowhead, to push any dirt out and not drive it in. If you cannot do this indoors, do it in your shower.

You can also do what you are doing, but you need to vacuum the filter first. Soak it in your laundry tub in a few inches of hot water and laundry detergent. Swish the filter around and let it soak for at least 10 minutes. Rinse the filter as mentioned above.

Stand the filter on one corner for five minutes then flip it over and repeat the drying process to allow as much drainage as possible before reinstalling it.

Q. Please, I would like to know the best type of caulking to use for an outdoor wood porch.

A. My vote is always for polyurethane caulking. There are several brands available nowadays, but the first one I became acquainted with in the late 1950s is Sikaflex-1a.

I have continued to use it after trying other brands that I didn't find as satisfactory. I realize that it is my own bias, and I am sure that other brands will do just as well.

You should be able to find Sikaflex in specialty building-product stores and online at www.ahharris.com. Home Depot carries Sikaflex construction adhesive in their masonry department, and I assume it's the same product with a slightly different name.

You are unlikely to find Sikaflex in most paint and hardware stores; it's mostly used by commercial contractors.

Q. Will you please help me find a way to clean soap scum from glass shower doors.

A. Try white vinegar applied with a sponge.

Q. I'm hoping you can help. I moved into my current apartment in 2006 and for the past couple of years we have been invaded by very small flying insects (gnats? fruit flies?). Several visits by an exterminator have failed to solve the problem. Can you offer a suggestion as to what we might try to eliminate these annoying little creatures? Would you be able to offer a source as to where they might nest and/or breed?

They seem contained mostly to the second floor on which the main living and kitchen areas are located but they do occasionally show up on the ground floor (garage, storage area) and third floor (bedrooms).

A. I suspect these small insects are fruit flies that are attracted to ripe fruit on kitchen counters or a composting bucket with a lid not tightly closed.

Q. I like your column! At your suggestion, I plan to install a Laing AutoCirc pump in my bathroom. Having provided the GFIC outlet, I went online to find the pump, but got overwhelmed by the wide variety available. Can you please do a column that sorts through some of the criteria in choosing one? Maybe even give model numbers?

A. The one I believe to be the most appropriate for residential use, and the one I had installed in our house, is the Laing ACT-4 Wireless Hot Water Recirculation Pump.

The pump should be installed under the farthest sink from the water heater.

Interesting comment from a reader: "Regarding the (June 3) column from the reader whose vacuum cleaner repeatedly tripped the house circuits, while this solution won't solve any electrical issue with the house, a quick fix is for the homeowner to purchase a lithium-ion battery run vacuum cleaner.

Ours (which happens to be Hoover Linx) is a life changer. No more fussing with the electrical cord, and vacuuming out the back of our car is so easy now. We have the basic model which is under $100 (available on Amazon). Our son has one with the attachments (works very well) for under $150. That reader should be very pleased with this solution."

• Henri de Marne, a former remodeling contractor turned columnist and consultant, is the author of "About the House with Henri de Marne" (Upper Access Publishing). He continues to take questions from readers for this column and his website, www.henridemarne.com. Email questions to aboutthehouse@gmavt.net.