Questions & Answers

We receive common and frequent questions regarding A/C Cleaning and Decontamination. We hope that you may find this page to answer questions you may have. Most answers come are directly from NADCA and the EPA.

How do you determine the need for HVAC System Cleaning and Restoration ?

HVAC systems should be cleaned when an HVAC cleanliness inspection indicates that the system is contaminated with a significant accumulation of particulate or microbiological growth. If the inspection shows that HVAC system performance is compromised due to contamination build-up, cleaning is necessary.

Often HVAC systems become contaminated during construction activities within a building. Newly installed HVAC systems should be clean before operated.

HVAC system inspections must be part of a building’s overall indoor air quality management program.

How often should my HVAC System be inspected and cleaned ?

HVAC Cleanliness Inspection Schedule. HVAC systems should be routinely inspected for cleanliness by visual means. The table below provides a recommended inspection schedule for major HVAC components within different building use classifications.

The inspection intervals specified in Table 1 below are minimum recommendations. The need for more frequent cleanliness inspections is subject to numerous environmental, mechanical and human influences. Geographic regions with climates having higher humidity, for example, will warrant HVAC system inspections on a more frequent basis, due to the increased potential for microbial amplification.

If the inspection of the air handling unit reveals contamination, then supply and return ductwork must be inspected at that time rather than in accordance with the intervals specified in Table 1.

Table 1. HVAC Cleanliness Inspection Schedule (Recommended Intervals)

What is inspected during a HVAC System Inspection ?

The cleanliness inspection should include air handling units and representative areas of the HVAC system components and ductwork. In HVAC systems that include multiple air handling units, a representative sample of the units should be inspected.

The cleanliness inspection shall be conducted without negatively impacting the indoor environment through excessive disruption of settled dust, microbial amplification or other debris. In cases where contamination is suspected, and/or in sensitive environments where even small amounts of contaminant may be of concern, environmental engineering control measures should be implemented.

Does a dirty system compromise performance ?

Heat exchange coils, cooling coils, air flow control devices, filtration devices, and air-handling equipment determined to have restrictions, blockages, or contamination deposits that may cause system performance inefficiencies, air flow degradation, or that may significantly affect the design intent of the HVAC system, shall be cleaned.

Does a dirty HVAC System effect your health ?

Heating, ventilation, and air conditioning (HVAC) systems have been shown to act as a collection source for a variety of contaminants that have the potential to affect health, such as mold, fungi, bacteria, and very small particles of dust. The removal of such contaminants from the HVAC system and home or business should be considered as one component in an overall plan to improve indoor air quality.

RESIDENTIAL CONSUMER QUESTIONS:

Frequency of cleaning depends on several factors, not the least of which is the preference of the home owner.

Some of the things that may lead a home owner to consider more frequent cleaning include:
- Smokers in the household.
- Pets that shed high amounts of hair and dander.
- After home renovations or remodeling.
- Prior to occupancy of a new home.
- Water contamination or damage to the home or HVAC system.
- Residents with allergies or asthma who might benefit from a reduction in the amount of indoor air pollutants in the home’s HVAC system.

The Environmental Protection Agency says that “duct cleaning services typically – but not always – range in cost from $450 to $1000 per heating and cooling system, depending on the services offered, the size of the system to be cleaned, system accessibility, climactic region, and level of contamination” and type of duct material.

Consumers should beware of air duct cleaning companies that making sweeping claims about the health benefits of duct cleaning – such claims are unsubstantiated. Consumers should also beware of “blow-and-go” air duct cleaning companies. These companies often charge a nominal fee and do a poor job of cleaning the heating and cooling system. These companies may also persuade the consumer into unneeded services with and/or without their permission (This Pricing is for RESIDENTIAL Consumers).

Interview as many local contractors as you can. Ask them to come to your home and perform a system inspection and give you a quotation.
To narrow down your pool of potential contractors, use the following pre-qualifications:

Make sure the company is a member in good standing of the National Air Duct Cleaners Association (NADCA).
See if the company has been in business long enough to have adequate experience.
Inquire whether the company is in good standing with your local Better Business Bureau
Get proof that the company is properly licensed and adequately insured.
Verify that the company is certified by NADCA to perform HVAC system cleaning.
Make sure that the company is going to clean and visually inspect all of the air ducts and related system components.
Avoid advertisements for "$99 whole house specials" and other sales gimmicks.
Ask if the company has the right equipment to effectively perform cleaning, and if the company has done work in homes similar to yours.
Get references from neighbors if possible. Ask you Resident or Property Manager