Funky AC Smell

[MikeVic]

A few days ago, I started smelling something funky (like BO) and threw out all my garbage, cleaning a bunch of stuff, etc and figured it would go away. I aired out my home when it wasn't very hot outside recently and it was fine.

So today is pretty warm, and I noticed the smell back again. I smelled some events when the AC was running and it seems to be coming from there.

I've had my ducts cleaned in late 2012, and changed the filter yesterday. I also checked the AC outside for any kind of dead animals or something, and don't see anything.

Is this just something I should call a general AC/heating company about to come by and check (and pay for)? I don't want to get my ducts cleaned right now if the better option is to get the source discovered first...

I haven't had to deal with this before, so I thought I'd ask FOFC. Thanks!

[stevew]

See if it still smells with only the fan on. Probably something dead in your ducts.

[Danny]

Sorry. I needed a place to hide out and haven't been able to shower in a few weeks

[stevew]

Check the returns as well.

[CU Tiger]

How frequently does your ac run?

Also do you have an air handler in the attic or crawl or crawl space/basement or a combo unit outside.

I'm thinking a clogged condensate drain line that's mildewed.....

[Warhammer]

It could also be mold on the AC coil. There are a number of issues it could be. How long does your AC run when it is on?

EDIT: you should not need to have your ducts cleaned frequently.

[CU Tiger]

Unless you are highly allergic and doing HEPA level filters etc its arguable that duct cleaning is worthless.

Now the reason I ask how frequently your system runs is I have friends in Buffalo that talk about their ac running "every few years"...in that circumstance I cab much easier see mold build up.

Mold on the coil structure was the reason for the comvi unit question.

[MikeVic]

I'll try the fan thing soon, thanks. Sorry, what are returns?

My unit runs multiple times per day, it gets pretty warm here in the summer. And it was running fine without smell around last week.

I don't believe I have anything other than the unit standing outside.

Would the drain line be the tube that runs from a small device beside my furnace, into a larger tube that takes water elsewhere? I believe my washer leads to this bigger tube as well.

To check the coil structure, would I take the outer shell off my unit outside and inspect it like that?

Thanks!

[CraigSca]

Returns are the vents, usually along the flooring, that supply the intake for your AC units. It sucks in air through these vents, cools it, and the pushes it out through your AC vents.

[CraigSca]

To check the coil structure, would I take the outer shell off my unit outside and inspect it like that?

Thanks!

I'm not sure, but he could be taking about the coils inside the unit itself. Meaning, the coils that the air filter are protecting. Sometimes, if the filters aren't cleaned or changed for a long time, all that crud gets in your coils and makes your AC much less efficient (and possibly moldy).

[CU Tiger]

Is your house on a basement or crawl space?

[CU Tiger]

Returns will be the large "ports" where the system sucks air.

Type Cally either in the ceiling or in a wall. This is the place where your filters go.

[Warhammer]

The two normal places for mold is the filter and the indoor coil. Those are the only two areas that moisture can really build up. If you check your filter and it is clean, that points to the coil. Depending upon how your system is set up, the coil is sitting above the blower.

[MikeVic]

Is your house on a basement or crawl space?

I have a basement.

Returns will be the large "ports" where the system sucks air.

Type Cally either in the ceiling or in a wall. This is the place where your filters go.

I checked the vents that run along the floor, can't really see far into them but sprayed some febreeze in them all just in case. I ended up doing this a couple days ago too. I did not check the intake vents in the walls, but I don't recall filters being htere from previous times that I've checked them. What is "Type Cally"?

The two normal places for mold is the filter and the indoor coil. Those are the only two areas that moisture can really build up. If you check your filter and it is clean, that points to the coil. Depending upon how your system is set up, the coil is sitting above the blower.

I replaced the air filter that is beside my furnace, and checked inside the AC unit that is outdoors and it looks clean. So I should find a coil somewhere in my basement that is connected to the AC outside...?

After I replaced the filter on Saturday, sprayed febreeze in the floor vents, and cleaned a bit inside the bottom portion of my furnace (where I can see the filter), the smell is still there but I'd say not as strong. Or maybe I'm just getting used to the smell. :p

When I did examine the areas around my furnace and replaced the filter, I noticed a bit of water around the area. I'm guessing this isn't something normal and I should get someone to examine the AC unit? Is it possible to leak or something? Or is this normal behaviour?

Thanks for all the help!

[CU Tiger]

Type Cally was apparenlty an autocorrect of typically.


if the intake returns dont have filters in them then you likely have all kinds of issues. Unless you have a very different HVAC system than I am used to. (I am an electrician not an HVAC guy... I can look at a system and figure how it works but am not familiar with every different type of design out there)


When AC runs in the summer, it creates condensation. This will drip from the air handler coil and be plumbed outside the house. If the handler is in an attic typically you just have a PVC drain that runs outside through the gable end. If it is in the basement it will usually run to some sort of pump. If this water cant get away it will back up until it sits in the air handler and will mold and mildew over time. All of the air that comes out of your vents gets blown through the air handler, that is how it gets cooled, if there is mildew in there it will pick up that smell as well.

In any case these drains are low pressure and very common to get clogged. Usually a quick blast witht he garden hose will clean them out. We have a condensate drain pump in our basement that we have to replace about every 3-4 years that costs ~$50/each. Likewise when it goes bad the water backs up and can mildew.

[Blackadar]

Lesson to learn - don't stuff dead bodies in your own a/c ducts.

[Dr. Sak]

If you have stairs in your house, then you are protected.

[MikeVic]

Type Cally was apparenlty an autocorrect of typically.


if the intake returns dont have filters in them then you likely have all kinds of issues. Unless you have a very different HVAC system than I am used to. (I am an electrician not an HVAC guy... I can look at a system and figure how it works but am not familiar with every different type of design out there)


When AC runs in the summer, it creates condensation. This will drip from the air handler coil and be plumbed outside the house. If the handler is in an attic typically you just have a PVC drain that runs outside through the gable end. If it is in the basement it will usually run to some sort of pump. If this water cant get away it will back up until it sits in the air handler and will mold and mildew over time. All of the air that comes out of your vents gets blown through the air handler, that is how it gets cooled, if there is mildew in there it will pick up that smell as well.

In any case these drains are low pressure and very common to get clogged. Usually a quick blast witht he garden hose will clean them out. We have a condensate drain pump in our basement that we have to replace about every 3-4 years that costs ~$50/each. Likewise when it goes bad the water backs up and can mildew.

I know what intake filters you're talking about, I think... they're like what you see in Walter's house in Breaking Bad? :)I just have a filter right by my furnace, I think that's supposed to do a similar thing...

I do have a pump right beside the furnace in the basement that has a tube taking the water outside. There could be something with this, I haven't changed it or done anything to it in the six years I've been here. Thanks, that points me to something to look at!

[MikeVic]

Lesson to learn - don't stuff dead bodies in your own a/c ducts.

Danny must have gotten trapped in there. :( RIP Danny.

[MikeVic]

If you have stairs in your house, then you are protected.

Oh yeah, that's part of my zombie plan for sure. Head upstairs and destroy part of the stairs. Fill up the tub with water and survive up there for a bit.

[CU Tiger]

I do have a pump right beside the furnace in the basement that has a tube taking the water outside. There could be something with this, I haven't changed it or done anything to it in the six years I've been here. Thanks, that points me to something to look at!

I dont want you to replace a good pump because I said mine goes abd often, I'd feel really bad if you did that.

But look at that tube and see if it looks moldy or if there is water on the ground around it. There should also be a test button on it or you can just pour some water into the intake as it should be float controlled/

[Warhammer]

The coil I am talking about is near the air handler with the furnace. Often times the ductwork above the coil will have condensation that will drip on the outside of the furnace. This is due to the humidity in the air. This is normally not an issue.

There is typically only one filter where the return enters the furnace.

Depending on the set up, To check the pump you can pour water in the pan. There is normally a switch that will turn on the pump.

[MikeVic]

I dont want you to replace a good pump because I said mine goes abd often, I'd feel really bad if you did that.

But look at that tube and see if it looks moldy or if there is water on the ground around it. There should also be a test button on it or you can just pour some water into the intake as it should be float controlled/

Yeah, I just meant that's something that seems to make sense right now. I won't replace the pump unless necessary, but there are two tubes coming out of the pump. One fairly clear one and one pretty gross-looking one. I think I'll replace those and see what happens, then go from there! I'm away this weekend but will start on this early next week. Funkiness lives on. :p

[MikeVic]

The coil I am talking about is near the air handler with the furnace. Often times the ductwork above the coil will have condensation that will drip on the outside of the furnace. This is due to the humidity in the air. This is normally not an issue.

There is typically only one filter where the return enters the furnace.

Depending on the set up, To check the pump you can pour water in the pan. There is normally a switch that will turn on the pump.

Thanks, there might be excessive condensation or something in that ductwork abvoe the coil, since there's water definitely dripping on the outside. I will check what CU Tiger suggested and also check this, since they both make sense based on the explanations. :)

Thanks guys!

I will report back sometime next week.

[Warhammer]

To compensate for the condensation you can dry the duct and insulate it. The insulation will act like a drink koozy so the condensation will occur further up the line.

[jaygr]

Quick question if I can hop on this thread, is replacing the fan blades on an older outside condenser unit something a layperson could do fairly easily/safely?

[cartman]

Quick question if I can hop on this thread, is replacing the fan blades on an older outside condenser unit something a layperson could do fairly easily/safely?

It depends. If they screw on, it is easier than if they are riveted on. Then there is the question of balancing the blades after installation. If you have problems getting ceiling fan blades to balance, the ones on the condenser are approximately 82.376 times harder to do.

[jaygr]

It depends. If they screw on, it is easier than if they are riveted on. Then there is the question of balancing the blades after installation. If you have problems getting ceiling fan blades to balance, the ones on the condenser are approximately 82.376 times harder to do.

Thanks for the reply. Does that go for the whole 1 solid piece (that includes all 4 blades) or are you talking about replacing only one blade? I'd be looking at something like this:BestBuyHeatingAndAirConditioning.com 13" Condenser Fan Blade Old Blade 4 Blades New Fan Blade 5 Blades Upgraded for more Air Flow (Rotat (http://www.bestbuyheatingandairconditioning.com/Merchant2/merchant.mvc?Session_ID=fed274d11aba301457e986f49930586d&Store_Code=BB&Screen=PROD&Product_Code=FAN01EW013A)

[SteveMax58]

It depends. If they screw on, it is easier than if they are riveted on. Then there is the question of balancing the blades after installation. If you have problems getting ceiling fan blades to balance, the ones on the condenser are approximately 82.376 times harder to do.
Heh....

1st thought: "But I've never had to do anything other than screw them to the fan assembly".

2nd thought: "Maybe its supposed to be quieter?" :lol:

[Warhammer]

Typically a replacement set of fan blades is only about $100, or at least was last I had it done. This falls into the easier to have someone else do it category for me.

[cartman]

Thanks for the reply. Does that go for the whole 1 solid piece (that includes all 4 blades) or are you talking about replacing only one blade? I'd be looking at something like this:BestBuyHeatingAndAirConditioning.com 13" Condenser Fan Blade Old Blade 4 Blades New Fan Blade 5 Blades Upgraded for more Air Flow (Rotat (http://www.bestbuyheatingandairconditioning.com/Merchant2/merchant.mvc?Session_ID=fed274d11aba301457e986f49930586d&Store_Code=BB&Screen=PROD&Product_Code=FAN01EW013A)

That one looks pretty straightforward. Probably all you have to do with that one is get the torque right on the nut.

My remembrances were from helping my dad fix a bad blade on our condenser unit back in the 80s. It was a rivet one, and it was a pain keeping the blade level so that the rivets would go in flush. Then we didn't get it balanced right, and it ended up destroying itself in about a week.

[Warhammer]

The concern is if the fan comes off, there is a risk that it can damage the coil, which means replacing the outdoor unit, which could require replacing the indoor unit depending on the age of the coil.

[MikeVic]

So the issue seems to have been the tube that goes from the coil part inside the ducts, above the furnace. The part of the tubs that connects to the duct (an elbow connection) was filthy, and a lot of gross water drained out once the gunk was removed. I don't smell anything anymore, so I think it's solved.

Thanks for the help!

[Warhammer]

If it was inside the tube, that should not have caused and odor outside the tube (it is a sealed system). Now if the coil was freezing and condensation was collecting on the coil, that could cause an issue.

Come to think of it, the elbow in question, was it copper or PVC?

[CU Tiger]

He is most likely talking about the PVC pipe drain tube.
WHich would have off gassed odor back into the coil and been picked up by air moving across the cooling coil as opposed to a clog being inside a cooling coil, which as you mentioned is sealed.

[MikeVic]

Sorry for the bad explanation, I think CU Tiger has it right. There's a metal pipe sticking out from the duct above the furnace... there is a PVC elbow connection and rubber tube going from that metal pipe down into the compressor that leads water out of my basement.

Once the PVC elbow connection was removed, the metal pipe that sticks out had a bunch of gunk in it. When that was cleaned, a lot of dirty water flowed out.

I didn't look at the coil at all.