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Tips for improving your AC’s performance

Tip: Vacuum out your floor registers and ducts regularly.Carolyn Franks/Shutterstock/Carolyn Franks

Q. We have oil heat and forced-hot air vents in each room — two floors, small home. My question is more about our central air conditioning. It is always two to three degrees warmer upstairs, which makes a big difference to me, not my partner. I am always hot, and he would never turn it on if it were up to him. Would cleaning the vents etc. allow it to work more efficiently, and would it help with allergies, mold, headaches, as advertised? Thank you for your opinion.

TERRI LOTEN, Marshfield

A. How old is your HVAC system? The ductwork? Do you have pets? Are you good about changing your HVAC filters? In my limited experience, and observations when removing ducts, most ductwork does not get that dirty. The grills, if they’re on the floor, tend to collect dirt, pet hair, and dust, however.


Vacuum out your floor registers and ducts regularly and change your filters. I use pleated media filters designed to collect more particles than the thin fiberglass ones. The pleats increase the surface area and make the furnace filters more efficient at capturing airborne particles. A pleated air filter with a medium efficiency rating can filter small to large particles. High-efficiency particulate air (HEPA) filters are also an option. They are worth the price, especially if you have allergies and/or pets. You may need to change the filter carriage on your system to accommodate these larger filters.

Mold sometimes grows in ducts, and this can be remedied with an ultraviolet light system.

Do you use an HVAC company that services your unit? The best advice I can give you is to seek out a qualified HVAC company and ask for advice and recommendations on improving your air quality and efficiency. There are some really cool high-efficiency systems out there that may suit your small house well. Good luck.


Q. I have five roof windows that are 30 years old, and I am very pleased with them. I installed them myself, and they still don’t leak. The fabric on the shades needs to be replaced, however, and none of the local companies I contacted will even talk to me about doing it. It seems like a simple task — get fabric, cut to size, then fasten it to the rollers — but I’m concerned about doing it accurately. Would appreciate any advice.


A. Funny, but you e-mailed me while I was wrestling with my skylight shades. There are companies that will custom make any size skylight shade for you. I ordered pleated skylight shades online and installed them myself. Pleated shades help reflect the sun’s radiant heat in summer and limit room heat from escaping in winter to maintain a comfortable interior environment. If you installed the windows, you definitely can handle swapping out the shades.

Rob Robillard is a general contractor, carpenter, editor of AConcordCarpenter.com, and principal of a carpentry and renovation business. Send your questions to homerepair@globe.com or tweet them to @globeaddress or @robertrobillard.