Alliance Air Quality Services

allianceairqualityservices.com

FAQ

How can I tell if my HVAC-System needs to be cleaned?
Look for dirt and dust visible on supply and return registers or a shadow on ceilings or walls surrounding the vents.
Odd smells, such as wet dirt, moldy odors, or “dirty socks” can point to a dirty air handler or open ductwork. If you dust your furniture and the dust reappears the next day, you can benefit from this service.
I have an allergy sufferer in my home. Will having my system cleaned help?
If your home or office is a problem area for that person, they might be sensitive to contaminants in the HVAC system. Often a dirty air handler is the culprit. A system inspection can pinpoint the problem and determine what corrective steps are required.
How often should I have my HVAC-System cleaned?
Typically, a residential system in good condition with proper filters in place should stay clean for three to five years. Office or work-space systems with high traffic or unusual conditions may require cleaning in as little as one to two years.
There are many variables affecting how quickly a system returns to a dirty state after cleaning. System age and condition, structural tightness of the space, traffic in and out of the home or office, and proper filter usage are just a few examples. The correct cleaning process and proper filter usage net the best results.
What should a complete service include?
All ductwork cleaned while under negative pressure from a separate recovery unit (not a vacuum cleaner).
While under a negative pressure, all ductwork (not just the branch runs) should be cleaned with some type of agitator, preferably with the help of compressed air.
The air handler should be cleaned completely. Attention should be paid to individual components, i.e. the blower, evaporator coil, and drain pan.
How can I tell if I'm talking to a competent contractor?
The representative should be able to answer your questions in detail, without making vague references to numbers and pet names for procedures. You cannot correctly clean a duct system by simply connecting a recovery unit to it or by fogging it with chemical agents. Also, be wary of sales pitches touting whole-system sanitizing or coating ducts internally to seal contaminants in place. These are not proven procedures and should raise suspicion on your part.
How much time will the job take and how much will it cost?
A single system in an average home (1-2,000 square feet) should take two technicians a minimum of four hours in a small home or apartment to six or more hours in a larger one. The price will range from $500 to $1,000, depending on system size, services offered, or if any repairs are needed. Most first-time customers are amazed at the amount of energy and time it takes to do this work correctly.
Multi-system homes or businesses require more time and are priced according to size and conditions.

Glossary of Terms

AHU
air-handling unit
air wash
a method of cleaning surfaces with high-pressure air in areas where aggressive mechanical agitation is not viable
air-handling unit
an assembly of equipment (typically fans, coils, and sometimes filters) for the treatment of air so as to control simultaneously its temperature, humidity, cleanliness, and distribution to meet the requirements of a conditioned space.
air handler
see air-handling unit
boot
often referred to as the vent, is the area behind a supply register where air enters the occupied space; typically located in the ceiling or floor
branch runs
smaller portion of the duct system connecting the trunk to the supply vents
diffuser
see register
evaporator coil
also an indoor coil; a device that is designed to absorb heat in the air in order to change the liquid refrigerant that flows through it into a vapor
flex duct
a resilient, round, inner-air tube wrapped with fibrous glass insulation and sheathed with an outer jacket
grille
a flat square or rectangular inlet generally made of metal and used at the entrance of an HVAC system to direct air into the return; often houses the air filter
HVAC
Heating, Ventilation and Air Conditioning
hard-pipe duct
round, galvanized-metal material used to construct trunks and runs in an HVAC system
main duct
see trunk
mastic
a pasty material used to seal gaps in ductwork; also used to seal insulation
media
the fine material of a filter that traps dirt, dust, mildew or bacteria
NADCA
National Air Duct Cleaners Association; a non-profit association who publishes standards and guidelines for the duct-cleaning industry
negative pressure
reverse movement of air in a duct system acting as a vehicle for source removal
package(d) unit
a heating and cooling system contained in one outdoor unit
plenum
an enclosed space in an HVAC system that houses the air before it is forced through the coil; the plenum is usually located behind the filters or sometimes attached to the AHU
recovery unit
machine used to create a negative pressure in ductwork and to collect and control the spread of contaminants dislodged during the cleaning process
register
a circular, square, or rectangular air-distribution outlet generally made of metal and used at the exit-end of an HVAC system to release, regulate, and direct air flow; usually located in the ceiling or floor
return-side ductwork
the portion of the ductwork where air is directed to the AHU to be sent back through the system
source removal
mechanical cleaning of system components to remove dirt and debris
split system
an outdoor unit combined with an indoor unit; typically a condensing unit and an air-handler
supply-side ductwork
the portion of the ductwork that delivers conditioned air to the occupied space
supply runs
see branch runs
trunk
larger portion of the duct system that is located between the AHU and branch runs
vacuum collector
see recovery unit
vent boot
see boot