We have a musky smell coming up through the heating vents. Also I have noticed that our ice cubes have been coming out with an odor, similar to the kind of odor and taste they get after sitting unused for a while. But this smell is with them right from the first day. I don't know if there is a connection. Also, in February we had a humidifier installed on our furnace which is only a year old. The house is only a year old. We had the furnace people out but they found nothing wrong, and of all days, the smell from the vents was not there that day. What could be causing this? And could there be a connection between the smell and the humidifier? Oh one more thing. The smell is also noticeable on my dishrags.

Where does the dehumidifier drain to? Does the hot water smell worse then the cold? I'm trying to separate mold from bacteria, it sounds almost like you have both. Mold in the air vents and bacteria in the water. Can you give me any more details? Tom

Hi - thanks for the reply. We have a humidifier which drains into the sewer. I can't really tell if the smell comes from the hot water too. I don't think so. It certainly does from the cold because of the ice. It's funny because when drinking the water from a glass it doesn't appear to have an odor that is noticeable. If this is a bacteria and/or mold problem, how would it have originated? The only things that are very predominant is the smell from the vents, the ice and the smell picked up on the dishrags. Thanks for any help you can give us.

"We have a humidifier which drains into the sewer. I can't really tell if the smell comes from the hot water too. I don't think so. It certainly does from the cold because of the ice. It's funny because when drinking the water from a glass it doesn't appear to have an odor that is noticeable."

Look in your sink cabinet at the icemaker connection. Savvy plumbers take the ice maker off the hot water supply. In the water heater the water sets and deoxygenates. This means less air bubbles in the icecubes giving you a clear cube and reducing the "milky" look. Since water will set in the ice maker line for long times it enters the icemaker at room temperature. So the water heater's not out of the equation yet. If your dehumidfier drains into the sewer with out being trapped than you have a direct connection to the sewer from your house letting sewer gas escape. Sewer gas is a health hazard to your familys health and the methane content makes it explosive.
Since there should be no connection between the vents and the water supply could there be a chance that we're looking at two separate problems?
Regards. Tom

My husband, who happens to me a retired plumber from way back, says that the ice cubes are coming out milky so the water heater probably isn't the problem there. And there is a proper trap where the humidifier drains. Is that right? Is that what you were explaining? I have done a mold test by putting a mold dish right into one of our heating vents. I guess I will know in about 48 hours if there is a problem there. I don't know - all I know is this smell is driving me insane. Luckily it is not noticeable when walking into the house.

Try putting a ice maker filter on the lines going tom the hum. And to the ice maker

"My husband, who happens to be a retired plumber from way back,"

I too am a retired plumber from way-way back. Let us know how the mold test comes out and the suggestion to filter the ice maker line's a good one.
Regards, tom

Well, the mold test came up negative. I happened to mention my problem to my neighbor and she said that she sometimes has the same odor. She claims it is just cinder gas that is normal when a house is on a slab like ours. We live in a detached cluster home development. Could that be the problem? Does that make any sense? Thanks for all your help, Rose C.

If you have ground water trapped under the house with little access to to air, it will turn foul, and the odor could work its way up through the slab. Likely to be the worst where you have carpet or tile rather than a sheet of something like vinyl. Of course, it could work its way into ducts under the slab and come out the vents. Not sure there is a good fix. You could start by checking your drainage. The ground should slope away from the house all around. The builder could have cut corners on that because the house is on a slab. I would regrade if you need to. Even cut a swale to drain water from the upper side.

If radon is a problem in your area, I would have the house checked. A system to remove radon might take the bad smell too.

Can't imagine that having anything to do with the ice cubes. In one of Tom's posts he said it could be a couple of problems. No clue on what the other might be.

Labman never ceases to amaze me with the scope of his knowledge.
"If you have ground water trapped under the house with little access to to air, it will turn foul, and the odor could work its way up through the slab."

This is one that I never thought of and I live and work in a area of all slab homes with a high water table. Kudos, Lab for bringing that to our attention.

Smell and taste problems are the hardest ones for a plumber to track down because there are so many places they can occur. With a leak you can see the water but with smells where do you start? Especially if they seem to come from all over. Labman has come up with a new and hitherto unthought of answer as to the source. Now if we could just come up with the solution.
Regards, Tom

You all have been so helpful with this problem. What a great forum. I originally said the mold test came out negative. Well, this morning when I looked the gel does have mold spores. It took over 72 hours for the results to service. The test instructions gave two options. I am going to try the second option which says to let the fan run continuously for ten minutes. I'm just curious. I'm really concern that we are breathing this in. Especially since I have a disabled granddaughter with severe respiratory problems. But how could mold grow in PVC pipe? Thanks again. Rose C.

Hi rose,

If you remember I said it sounded like you might have two problems. Mold in your vents and bacteria in the icemaker line and icemaker. Next test the ice cubes for bacteria. Regards, Tom

That's is exactly what I'm going to do. I did notice when I bought the mold testing kit that they also sell a bacteria kit for water. I am definitely going to buy that today.