# Horrible Home Odors: Fixing a Foul High Efficiency HVAC Unit - Link: https://greenlivingguy.com/2019/05/horrible-home-odors-fixing-a-foul-high-efficiency-hvac-unit/ - Published: 2019-05-04T19:46:22-04:00 - Author: greenlivingguy There are some problems which can make your HVAC give off a horrible odor. That which is sometimes this odor gets referred to as _dirty sock syndrome. So _we all know how bad that can be sometimes. If you switch on your HVAC and you immediately notice that there is a distinctly unpleasant odor in the air stop. Because this is something that [licensed technicians](https://www.griffithenergyservices.com/) are used to contending with and know how to fix _dirty sock syndrome_. ![Hvac dirty sock syndrome](https://i0.wp.com/greenlivingguy.com/wp-content/uploads/ 2019/05/pexels-photo-266896.jpg?resize=150%2C150&quality=52&ssl=1 "pexels-photo- 266896 - The Green Living Guy") #### **Bacteria to blame** The root cause of those foul odors. Odors that are therefore assaulting our nostrils: bacteria. Bacteria can grow in your HVAC system due to the fact that the coils used in your system. It can become both cool and damp, which helps to create optimum growing conditions for bacteria to grow. The end result of allowing this bacteria to flourish. Because when you switch the heating on, the unpleasant odor generated by the bacteria fills the air. Then and only then you end up with what is accurately described as a dirty sock smell. ### #### **Several scenarios** There are several different scenarios where a foul odor could be the end result. They are such as when the outdoor temperature falls below 40F. Then the HVAC unit switches to defrost mode. This creates a smell of mildew in the air and there is also likely to be a noticeable nasty odor when you decide to switch on the air conditioning after the heating has been turned off. **Mold and moisture** One of the most common reasons why an odor becomes apparent is down to the fact that moisture has subsequently spawned mold. [Mold](http://www.moldbacteriafacts.com/) can settle on the evaporator coils on your unit and also in some other places like the drip pans and drain lines as well as the surface of the liner. The odor you can smell is a good indication that mold is present in your HVAC system. So although you can smell it coming through your ventilation system, the source is an unpleasant slimy sludge. One slimy sludge happily feeding off the moisture in your unit. ![HVAC ](https://i0.wp.com/greenlivingguy.com/wp-content/uploads/2016/06/rocket- mass-heater-warm.gif?resize=300%2C300&ssl=1) #### **Call a professional** There a health issues that need to be considered before attempting to tackle this problem yourself. Also and that is why in most circumstances. So it is better to call in an HVAC professional to assist. Therefore unless you have plenty of experience yourself. A trained technician will be able to trace the source of the mold and fix the problem before turning on the unit again. **Problems with your ducts** It is also worth saying that the source of your odor problem may not actually be unit itself. So even though it may seem to coming from there. If the unit has not got a mold problem, it could be that debris and moisture. Debris and moisture has been allowed to build up in the ductwork. It is possible to trust your sense of smell and you may be able to pinpoint the exact location of the odor by identifying where the strongest scent is coming from. If it is the ductwork, it is often advisable to get an HVAC specialist to clean the ductwork to ensure that the problem is eliminated. The easiest way to avoid suffering from dirty sock syndrome and prevent bacteria from taking hold, is to have your system serviced and cleaned regularly. Rebecca Potter is a home improvement consultant. She likes to write about her experiences online. Her articles can be found mostly on home improvement and DIY sites. ![author avatar](https://secure.gravatar.com/avatar/df91669667126e1290c21ee0342c386e2da19d588d4d9ca6560bd82ed59a9641? s=300&d=monsterid&r=g) greenlivingguy The Green Living Guy, Seth Leitman is an independent power producer, a green living expert, and Editor of the McGraw-Hill, TAB Green Guru Guides. Seth is also an Author, Radio Host, Reporter, Writer and an Environmental Consultant on green living. The Green Living Guy writes about green living, green lighting, the green guru guides and more. Seth's books range from: # Build Your Own Electric Vehicle by Bob Brant and Seth Leitman (2nd and 3rd editions) # Build Your Own Plug-in Hybrid Electric Vehicle by Seth Leitman # Build Your Own Electric Motorcycle by Carl Vogel # Green Lighting by Seth Leitman, Brian Clark Howard and Bill Brinsky # Solar Power For Your Home by David Findley # Renewable Energies For Your Home by Russel Gehrke # Do-it-Yourself Home Energy Audits by David Findley # Build Your Own Small Wind Power System by Brian Clark Howard and Kevin Shea # and more green living books to follow. [See Full Bio](https://greenlivingguy.com/author/greenlivingguy/) [ ](https://greenlivingguy.com/author/greenlivingguy/)