Q. Our forced air oil-fired heating system is 35 years old, and over the years it has emitted a shrill howl in B flat, on and off. Sometimes it cycles three or four times a day. It tends to howl when the oil burner is off, so it must be in the blower and in the ducts. Have you heard of such a thing?
LEE ENGLER AND INGE THORN ENGLER, WESTON
A. I have heard of howls, squeals, moans, buzzes, hums, and every other kind of sound from heating equipment, electrical circuits, stereos, the wind, and this is the first one in B flat. Inge played that note on her violin, and while it is a high quality, benign sound, B flat has a certain annoying quality.
Have you had your dealer check it out? If you did, he certainly wasn’t much of a help. Hot air heating systems deliver heat through ducts, by way of a blower motor, and dampers, which allow the householder to increase or reduce the flow of air. One or more of these ducts may be a little open or a little closed, creating a small opening similar to a whistle, hence that B flat. If you made the opening a tad bigger, you’d get a lower note. You can have an experienced heating man inspect all those round ducts and dampers for proper operation. They are, or should be, readily seen and accessible in the basement.
But first, have your dealer check that blower motor, which I think is the culprit. I think replacing that motor and checking all bearings in the motor and blower will do the trick. Or it’s a poltergeist.
Q. I was hoping you could tell me if a carbon monoxide detector would be able to pick up gas from a gas oven?
RICH HORNBLOWER, BOSTON
A. Gas does not produce carbon monoxide until it burns, so no, a carbon monoxide detector cannot detect unburned gas. You need a separate gas detector; check with First Alert or other manufacturers. In fact, it is better to have separate detectors for smoke (and heat), carbon monoxide, and gas.
Q. My oil tank is 45 years old. The previous owner said he installed a lining in the tank. Is that enough to delay replacing it? Have you heard of Leak Seal, used to extend the life of oil tanks? How much would a new tank cost?
KEN PETERSON, SOUTH WEYMOUTH
A. I have heard of a lot of things, designed to cure a lot of problems, but I also am skeptical of all or most. A liner for a standard tank? I don’t think so. Leak Seal? It’s probably not worth trying in such an old tank. Your only recourse is to replace that tank immediately.
It will cost about $1,800 to $2,000 to drain the oil, cut up the tank for disposal, install a new one, and fill it with the saved oil.
Muffler for a generator
Mabel Walker of Watertown, N.Y., called to tell the Handyman how she quieted a natural gas generator that someone wanted to put a high fence around to keep the noise down: “I had a mechanic install an ordinary car muffler on the exhaust pipe, and it works very well. No catalytic converter needed.
Q. As new owners, we had an exhaust fan installed in the bathroom last summer, with the pipe going through the roof. A nor’easter came along and water went right down through the pipe and fan and into the bathroom. How can we stop it?
LORI TSURUDA, RANDOLPH
A. Have a cone-shaped, hat-like cover put on top of the pipe, or install an upside-down U-shaped extension on the pipe.
Q. I was told by a contractor that they wouldn’t do chimney repointing/waterproofing if below-freezing temperatures were forecast because the mortar wouldn’t cure properly. We had the work done by someone who has worked for us in the past. Unfortunately, the crew he sent came late, worked in the dark under lights, and missed several spots. He is sending them back to repoint the rest of the chimney. The forecast is for 23 degrees overnight tonight. Am I correct in asking him to come next week when the forecast low is above freezing?
A. You are correct. Working with mortar and concrete must be done when temperatures are above freezing. Even a little below freezing can ruin a job. And 23 degrees is strictly taboo.Peter Hotton is also in the g section on Thursdays. He is available 1-6 p.m. Tuesdays to answer questions. Call 617-929-2930. Hotton (firstname.lastname@example.org) also chats online 2-3 p.m. Thursdays. To participate, go to www.Boston.com