I have the Dirty Sock Syndrome with a brand new A/C unit. Live in Florida. Go from heat to a/c and the smell is unbearable. First thought is it smells like stinky feet, dirty socks, wet dog. But as you smell it, it smells like some wet metals I have smelled. Some costume jewelry that has gotten wet. Aluminum cans that got wet in recycle bin that was closed up. Something like that. I see all the answers are about bacteria and mold on the evaporator coil, needs to be cleaned again and again, etc. What I don't understand is why didn't my old A/C unit EVER smell? Why suddenly so much bacteria & mold that would create this horrible smell on brand new A/C unit? Wouldn't there be more bacteria and mold on an older A/C unit? This smell has made me sick. I can't use my brand new A/C unit.

When you actually discover the exact answers to all those questions I sure someone will buy the answers off you. This have been going on for some time and some attribute it to the oil like coating that is sprayed on the coils as a presertive/whatever. Some contractors are actually pressure cleaning the coil with a acid base cleaner BEFORE they are installing them. Many post this as a cure but I really do not know about that.

If it is a brand new unit let the contractor that sold and installed the unit fix the problem and also contact the local distributer/factory and complain real loud but nice. Good luck.

Quote:

---

Originally Posted by hvac1000

When you actually discover the exact answers to all those questions I sure someone will buy the answers off of you. This have been going on for some time and some attribute it to the oil like coating that is sprayed on the coils as a presertive/whatever. Some contractors are actually pressure cleaning the coil with a acid base cleaner BEFORE they are installing them. Many post this as a cure but I really do not know about that.

If it is a brand new unit let the contractor that sold and installed the unit fix the problem and also contact the local distributer/factory and complain real loud but nice. Good luck.

---

Thank you so much for your quick reply about this problem concerning these evap coils. If all in your field had the open mind to this problem that you seem to have, it would probably be solved by now.
When many A/C guys use the syndrome to cause homeowners to think the smell is coming from their bacteria, dogs, lifestyle, etc. they are able to sell them more and more uv lights, air cleaners,replace ducts etc. and take advantage of the situation. When homeowners have done all these things and the Dirty Sock Syndrome is still there, the A/C companies lose all credibility and rightfully so. The one common denominator in this, is it happens when new unit or new evap coil is installed.
From talking to others, realtors, etc. have smelled it in brand new homes, new a/c, new ducts. etc. that have never been lived in. Just by switching unit back and forth from heat to air to make sure unit is working. No bacteria or mold is found. But smell is unbearable.

If it is from air flow set too high causing water in the ducts creating mold, why is no mold is found in the ducts? If it is the oil put on coil by manufacturer, the oil would eventually be washed off with the constant washings of the coils and smell would not return. Again, the main response most homeowners are given from their a/c company is , it is your bacteria and mold causing it. Again, why more mold & bacteria in brand new A/C unit than on old A/C unit with naturally much more bacteria and mold?

It has got to be something in the metal the evaporator coils are made of that is causing this.
It is not just an annoying smell. It is making many people sick. Coughing uncontrollably, etc. People with breathing problems and weakened immune systems are being hospitalized because they got a new air conditioner!
When the stigma and embarrassment used against the homeowners is exposed and they see that it is not their bacteria, dogs, etc. causing this smell, the class action lawyers are going to have a field day.

Hopefully HVAC dealers will demand the manufacturers be held responsible before all involved in selling these things are held responsible.
As far as, the dealer that I bought mine from... they have done nothing but give me the run around. Schedule appts. And not show up. Or show up 2 hours late as I am leaving for work. I guess they plan on doing this until the 2 year warranty runs out. I am going to have to take legal action because I cannot live in this house and use the A/C after they installed this new unit.
I certainly don't have the answers as this has just happened to me. All I can suggest to start is, all who have bought a new HVAC unit or replaced a new evaporator coil and have this horrible smell soon after purchase, don't let them intimidate you or embarrass you. Keep all paperwork generated from service calls,etc. Note any breathing problems, illnesses etc. after purchase of new unit. Get as many people as you can to witness this smell, that were in your home prior to new purchase that know this smell was not in your home before you purchased the new HVAC system. Complain to BBB, to local news stations, on the internet, to dealers, manufacturers, etc. Keep your eyes open for class action lawsuits.
This has gone on too long for unsuspecting homeowners buying a new HVAC system or replacing a evap coil that has this syndrome. It should be called Defective Evaporator Coil Syndrome instead of Dirty Sock Syndrome.

Again, I appreciate your response and having an open mind to the cause of this problem other than just blaming the homeowners as many of the professionals that people have bought from, have done. You are a credit to your profession.

As a professional in the business, have you found any specific brand that has never had a reported case of Dirty Sock Syndrome in a new HVAC unit?

As a professional in the business, have you found any specific brand that has never had a reported case of Dirty Sock Syndrome in a new HVAC unit?

No but some manufactures have used a Teflon type coating to try and solve the problem. Now the coating is not exactly Teflon but the exact trade name escapes me at this time. We did some testing at the university and did find that the coils collected mold and mildew along with other dirt from the house but could not pin point the exact cause to be sure. What is known is that if the coil is cleaned well the smell stops for awhile so it does prove that the copper and aluminum along with the brazing alloys are probably not causing the situation.

One of my personal cooling coils in my home is about 30 years old and it will smell when first started in the A/C mode but abates quickly and the odor does not come back for the rest of the season. The other 2 cooling coils about the same age do not have that problem so it is also a mystery to me. The dirty sock smell is not new by any means.
Z

Boy I wish mine would abate quickly. It starts almost immediately when switch to A/C. No smell from heat. The smell intensifies over 3 day period if A/C stays on then starts to subside. But the smell is left lingering in sofas, clothing, etc. By day 2 of A/C on, you cannot be in this house. It is unbelievable. I have never experienced anything like this.
It has been unusually cold here at night & hot in the daytime. I would rather freeze and roast than smell this until something is done.

Our a/c guy came out and said the mildew smell comes from a dried out pipe and happens in the winter when its dry. He went up and filled a clear elbow with water to stop it, so easy to fix. On the elbow there's a cap that you can pop off and instructions for how to use and its purpose. If you can't find it then call someone, we got tired of the sewage smell filling our house.

Anything man made most likely has Volatile Organic Compounds ( VOC's) : Many VOCs are dangerous to human health or cause harm to the environment. VOCs are numerous, varied, and ubiquitous. They include both man-made and naturally occurring chemical compounds. VOCs play an important role in communication between plants. [1] Anthropogenic VOCs are regulated by law, especially indoors, where concentrations are the highest. VOCs are typically not acutely toxic, but instead have compounding long-term health effects. Because the concentrations are usually low and the symptoms slow to develop, research into VOCs and their effects is difficult. Old condensate drain pans were made of metal and the would rust and crack causing condensate leaks. They are now made of high temperature 1/8 inch Plastic with a sheet metal heat shield. The Evaporator coil sits three inches above the heat exchanger. When there is a call for heat the burners will come on heating up to 160F the fan ramps up and the Temperature drops to 145F and is forced convected throughout the dwelling via duct work. This being said Cleaning the new evaporator coil before install with Nu-Calgon Evaporator foam cleaner and the rinse it down with luke warm water ensuring that the rubber plugs are still in the vapor and liquid line ports. It is vital that the tech does not get and water in these lines. The coil comes factory purged with dry nitrogen which is an inert gas. Wipe down wet spots and allow to air dry for a couple hours. After the Certified HVAC Tech installs the coil there will still be a "New Car" smell for a day or two. Turn the T-Stat up to 80F and open all your windows and turn on all of your exhaust fans. Yes it will cost you some money in heating cost but the smell will go away faster.

When you are thinking of getting a new A/C always ask your friends who the went with and always get three or more quotes. Ask them to give you a quote for there high end unit and their low end unit and compare with the other two companies. There is no such thing as a bad unit, all units these days are built by robots with all of the same parts, the only difference is cabinet wall thickness, type of motor, and type of compressor. The Higher SEER rated A/C have more coil volume for better heat rejection and absorption. Every HVAC/R company are "Dealers" like "Car Dealerships" if you go to chevy they will say they are the best and ford's are all junk and vise versa. The High end Units are Carrier, York, Coleman, Lennox, LG Ect.. They all have Sub Models like Payne, Trane, Comfort Aire, Keep-rite Ect.. For the Company to sell the High end models they have to be a "Contractor" and have a License agreement with the Manufacturer. So when you get three quotes one company will quote you a Carrier and will say nothing but good things and same with the other dealers with their House brands. What I'm getting to is that "there is no such thing as a crappy brand of A/C there is just Crappy installers that are cutting corners and not following the crucial steps to make the unit run properly. You can spend thousands of dollars on 20 SEER A/C and the Installer can make it run like a 6 SEER "The efficiency of air conditioners is often rated by the Seasonal Energy Efficiency Ratio (SEER) which is defined by the Air Conditioning, Heating and Refrigeration Institute in its standard ARI 210/240, Performance Rating of Unitary Air-Conditioning and Air-Source Heat Pump Equipment.)" When you get three quotes and say one is $5,000 and the second is $3,500 and the third is $2,500. The first thing the homeowner thinks is the first guy must be ripping me off and the third guy is doing me a favor. Well is TOTALLY the COMPLETE opposite. The First company is fully qualified, licensed, insured, reputable, competent, safe, quality and they will try their best to install the product as close to manufacture specification as the can and they won't just give up when a problem is to hard to solve. The third company will come in with a laborer and a semi-qualified apprentice install used parts and marked down units that might have been scratched or dropped they won't follow proper installation steps and the will probably do it in half the time. Well that because they installed the A/C just good enough to cool. What about all the other stuff they missed. (Delta T Calc, Heat Load Heat Gain Cal, Super heat Calculations, Sub-cooling Calc, Wet-bulb/ Dry-bulb and RH removal, is the unit secure, is it level, did they seal the duct work, did they clean up after themselves, did the purge with dry nitrogen while they were Brazing, Did the evacuate the Unit below 500 Micron and hold it for 20 min to ensure it didn't rise past 700 microns, did they do a triple dry evacuation with dry nitrogen, Did they pressure test to 150 psig and check for leaks with soap and bubbles, Did the insulate the whole suction line or only the portion you can see. Did they even change your line set and Evap? There are so many questions that home owners don't know how or what to ask. And that is why there are so many problems with the relationship between HVAC/R Technician and Customer. To install a A/C Properly 100% It takes time, time is money, patience, skill, and trade knowledge and the willingness care about the customer is what cost $5000.

Any Questions?

Oh yeah, the mold smell. If you are in the geographic of the USA and Canada that requires Heat and Cooling than this is for you. When we heat our home in the winter the cooler air in our home is drawn in through the return air duct, filtered or cleaned, boosted via Indoor fan, Heated and then (if your home has it) humidified. When a volume of air is heated from 70F to 150F and then mixed with ambient air the characteristics of they air change. If you have a cubic foot of air at room temperature and then heat it to 150F the molecules that make up "air" move further apart thus taking up more room. So if you have a volume of a 1000 Cubic feet of air at room temperature and then heat it the air will be taking up more space. So if you had a Relative Humidity of 55% before you heated the air and then heated the air but did not add moisture via humidifier then your dwelling RH would drop to around 30- 35%. This will cause dry nasal leading to cracks in your nose and will cause infections also you will find that you will have frequent static discharges. If you have hardwood floors then they will retract depending on the type of wood.

In the summer we take 80F or 90F Air and Cool it mechanically with a Central A/C. An Air conditioner is a closed loop system that takes heat from a place where it is not desired and moves it to place where it doesn't matter. (Outside) Sub-cooled Liquid Refrigerant goes through a metering device dropping the pressure causing it to be 75% Liquid and 25% Vapor, It then travels through the evaporator where the heat from your home passes through the fins on the coil and heats up the refrigerant (Evaporate) 100% Vapor exits the evaporator through the suction line, The system has to choke or flood the evap to sustain a constant super heat to ensure that the suction line brings back 100% vapor, it then travels travels back to the compressor, the compressor has two functions 1) Raise the refrigerant from a low temp vapor to a high temp vapor 2) Circulate oil through the whole loop. The refrigerant the enters the Condenser as a high temp, high pressure super heated vapor, the out door fan turns on blowing out door ambient air over the coil lower the temp turning the R to a High pressure high temp sub cooled liquid, exits the condenser passes through the filter dryer and back to the metering device and repeat until the T-Stat is satisfied. >>> the suction line is insulated for two reasons, we want super heat for compressor safety but we don't want too much so we want to avoid heat gain from the evap to the cond. Secondly the ambient air that comes in contact with the cold line reaches dew point and will cause the line to sweat or frost.

Getting back to mold when we cool a Cubic Foot of hot air the molecules get closer together raising the RH so much that the air can no longer hold the moisture. The air is warm the coil is cold (40F) so the evap is designed for the condensation to run off the fins into the condensate drain pan, sloped towards the drain line and into the drain.

If you evap isn't draining quick enough the slope might not be 1/4'' Per Foot (Ignore this tip if you have a prefab case coil, the slope is factory set) or depending on the make, model, location of Evap it may or may not require a condensate trap. When the indoor blower motor is on depending on where the evap is it will either cause a positive or negative drain pressure, a trap allows condensate to drip freely with out restrictions from pressure differentials. It may also no have a condensate air vent. If your tech can't find why the condensate isn't draining properly tell him to flip to page three in the installation manual, it tells you step by step what is required.

To avoid coil frost ensure the indoor fan motor is wired on High for cooling and change filter as per manufacture specs and check monthly, raise to a light if you less than 50% light through the filter change it. Don't block of registers or difuzers and pull furnature away from the wall to prevent blocking return air grill. Also do not use those stupid filters they sell at the hardware store that go into the register, it just restricts air flow. If you have a programmable T-Stat don't have a Delta T greater than 7 degrees, Also if you suspect lack of air flow for the size of you A/C put a needle thermometer in the return duct and one in the supply above the evap while the A/C is on there should be a Delta T of 20 dgrees +- 5. If it is higher or lower your fan might not be on the right speed or your A/C may be undersized or low on refrigerant, dirty coil, dirty filter, lack of return air. Any ways.

If any one has questions feel free to write me, I will give you an honest answer.

There is a chemical p - -antiseptic like smell from a new frigidaire window unit - make me very sick -

EPA has a website about spraying antimicrobials (ie pesticides that kill mold) on some units or systems and says safety had not been determined.

I have TWO HAIERS and the had no chemical smell, but this Frigidfaire is dangerous - and worse they won't tell me what it iss- and that shold be illegal.

Sorry I usually spell well but I am SIICK FROM THIS SICK AC ---- NEUROTOXIC - EAR CLOSED UP -- SHAKY - WEAK - IRRITABLE.

EPA SHOULD STOP THIS AND FRIGIDAIR SHOULD BE CALLED OUT ON NOT DISCLOSING THIS TOXIC CHEMICAL

My new LG (window type) A/C have this awful smell, and not organic, but a metallic/chemical smell, almost bitter like. It's been running for two weeks, and I have done the usual stuff, lemons, clean the filter etc.
But the smell is still ongoing, I am going to try the a odor remover for car A/C and see if this works.
If anyone have something that works, please share, its unbearable.

T

What I did 2 days ago is move my auxiliary heat strip on the return side of the unit so that the temperature would get high enough to kill the bacteria that builds up in the coils and so far it has worked. Took me about 2 hrs. I have a 2yr old tempstar package unit 3ton. I could not believe the smell of a brand new unit had put off and the many cases that are out there. It is only in the units that are more efficient and the aluminum strips are closer together. So I guess try it. Who ever has manufactured this problem of a more efficient coil should be responsible I believe. 3rd day found out that it definitely helps but not perfected. I have to bump the temp up so that the heat strip will come on with the evaporator coils to reach a killing temp again. It is 21 degrees out side this morning.

When I read the original question I was amazed that someone has the exact problem as myself. I described it to HVAC guy as a wet metallic smell. It's winter and there is no condensation on the coils. After doing all his tests the technician pretty much said I was crazy. The Evap Coils have been cleaned with bleach water, rinsed, and sprayed with Evap Fresh by NuCalgon. I cleaned blower motor fins. I removed and insepected about half of the duct work. I cleaned and disinfected just about everything I could take apart. In the summer I disinfect the evap drain tube and in the winter I remove the tube and plug it. The smell is not consistent. I seem to smell only when unit turns on and only for 20 seconds. Its not strong but if I'm standing close to a vent my eyes will burn immediately and a metallic taste in my mouth. This has been going on for more than a year. I have chronic stomach, sinus and upper respiratory problems during this time. I believed my health issues were related to my genetics but now convinced they are attributed to the HVAC unit. Any other suggestions would be greatly appreciated.
A question to any HVAC repair persons that might read this. Is it possible for any oil leakage from Evap coil that cannot be seen or detected. Maybe a small leak only when the machine clicks on. It has passed a pressure test. The repair man has been here twice in a year to repair a faulty fill valve and a blown solder joint. But that was on the outside coils. The unit is a Lennox about 6 years old. If I had the means I would move out of here tomorrow.