when ever i turn on my A.C at home, i get a sewage smell in the rooms near by and in the bathrooms?

Question

for the guest room there's an A.C. unit (Carrier) up on the roof, when i turn on the A.C. i get a smell from the unit ducts that's like a load of sewage and also in the bathroom because it's connected to it. Same thing for the rooms upstairs. The house is new so i doubt the ducts need cleaning.

Answer 1

You probably have some foul water in the condensate pan, and maybe a clogged drain line. Clean out the pan and drain, and then maybe have the pan coated with a coating to prevent the problem happening again.

Or, possibly, animals living in the A/C unit, or dead animal in the A/C unit.

Answer 2

When you say the unit is on the roof, do you mean it is a package rooftop? (the whole unit is on the roof, not a split system condenser).
If so, the unit may be next to a sewer waste vent sticking out through the roof and air is leaking through door cracks on the unit or there is actually an outside air damper to introduce fresh air into the unit. Vents should be 25' from fresh air inlets on A/C units. You may have to extend the vent above the unit with a Fernco band (a rubber coupling) and a piece of PVC.

If it is a split system, the condensate may be tied into the sewer drain (illegal). If the condensate trap on the air handler is dry, it will draw sewer gases up not the unit since the condensate on the unit is probably on the negative side.

If neither of these, I would have the unit checked out to see what else it could be (dead animal in duct, etc.)

Answer 3

Birds perching and pooping on your unit followed by a rain can cause this problem. A strategically placed plastic owl will end the perching. Use a garden sprayer with a mixture of water and household bleach and thoroughly spray the unit. This should fix the odor. There is a chance an animal entered and died causing the odor. This should never happen with a properly installed system.
If you find no bird butt bullets and since you say the home is new, up to 50 years, you should call your General Contractor or the HVAC contractor because absent the bird poop their installation is faulty. There should be no condition to cause this had the system been properly installed. If one of the stand pipes on the roof is in close prevailing wind proximity to the unitcan be another possible cause and install error.
Not to scare you, f.y.i. there is a BLACK MOLD that can cause GRAVE ILLNESS when pushed through the forced air ducts and may be present. A timely system inspection will be in order. If your contractor is unresponsive call a local reputable company to inspect and document the system. Take your findings to the unresponsive contractor and if they put you off...don't threaten...take them to court. They will end up paying all the costs and as will happen, one more small business will be out of business.

Answer 4

The condensate drain from the A/C unit is connected to the drain in your house. If the traps dry out then the sewer gas you smell is being forced into your house through the traps.

Try putting a couple cups of water down the drains. This may be the easiest way to solve the problem.

If this doesn't work you need to have the condensate drain on the unit trapped. The drain on the A/C unit would have to have a "P" trap installed in the condensate drain.

Answer 5

Find the condensate drain line and check to see if it is plugged. If so, the unit istself is probably flooded and the standing water is feeding bacteria. AC units have lots of problems with drainage lines plugging up.

Answer 6

a/c condensates and can get mold into the unit, may need cleaning??the unit not ducts.

Answer 7

its probally because your "SATAN" and you live in the depths of hell, where the smell of condemened souls fill the air. Really, satan as a screen name? Seriously, i dont have a clue, i just saw your name and.........