An odor coming from an air conditioner may mean that the unit’s coils and cabinet need a deep cleaning.

Each year, thousands of Arizona residents email or call Rosie Romero’s radio show with questions about everything from preventing fires in their chimneys to getting rid of tree roots invading their sewer system. His goal is to provide answers that suit the specific lifestyle wherever someone lives in Arizona.

QUESTION: I have a house that is only two years old, and I have been having continual problems with my air conditioner ever since I moved in. At first, I had trouble with the condensation line because it was plugged. Most recently in April, I had a leak. Then there were more problems with the condensation pipe. Now, this month, I can smell a chemical odor with a sweet tinge to it when the AC runs. Up in the attic where the air handlers are, there is brown rusty water in the drainage pan. They put in a new pipe and did a general cleanup, but the smell continues. What should I do?

ANSWER: The contractor probably needs to wash the coils and the cabinet in the air handler. The whole unit needs scrubbing down. I know you’re getting impatient and you want to get a second opinion, but you shouldn’t give up on the original AC contractor, hired by the builder, because your unit is still covered by the new home warranty. Put the whole situation into writing and send a letter to all parties. That way they’ll know that the warranty will last for another two years. That’s because warranties are extended from the time of service if that service took place while still under warranty.

Q: I have lived in Tucson since 1979 and I’ve never had scorpions until a couple of years ago. At first I found a couple of them in my bathrooms. This year, I’ve had four or five of them in my house and some in the backyard. How are they getting into the house and how do I get rid of them?

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A: As a home gets older, weather stripping wears down around doors and windows. If you can see light coming in under your doors when you’re in the house, you need to replace your weather stripping. Work on sealing the windows as well. Check under your pavers and rake up leaf litter. Some people like to spread diatomaceous earth around the perimeter of the exterior of the house to stop scorpions. You don’t want to overdo this process by putting big piles of earth around your house because scorpions will avoid it if they can see it. Just put down a thin trail so that they will crawl into it. An exterminator can help by sealing up your home and treating the perimeter with pesticides to scorpions from gaining entry.

Q: Can I stop my mesquites from dropping pods all the time?

A: Yes, there are products available to prevent “fruiting” in trees like mesquites. They will significantly reduce the dropping of seed pods. But the application must be timed right and should be done in the spring by a professional tree service.

For more do-it-yourself tips, go to An Arizona home building and remodeling industry expert for 29 years, Rosie Romero is the host of the syndicated Saturday morning Rosie on the House radio program, heard locally from 8-11 a.m. on KNST-AM (790) in Tucson and from 9-11 a.m. on KGVY-AM (1080) and -FM (100.7) in Green Valley. Call 888-767-4348.