Leaking Ductwork May Be Cooling and Heating Your Attic

THE BAD NEWS:

• Old ductwork may not have been properly sealed when installed, or the seals have failed over time.  This is equally possible for nearly new ductwork.
• Improperly installed, or undersized ductwork may result in airflow reduction (less air coming out than going into the system).

THE GOOD NEWS:

Determining if this condition exists is easy.

When looking for HVAC service

HVAC Service

Service Areas

• Allen
• Coppell
• Garland
• North Richland Hills
• Richardson
• Rockwall

What Does A Static Air-Pressure Test Tell You?

Static pressure is the measure of the Air Leakage OR Airflow-Resistance within the duct system. 

How An Air-Pressure Test Works:

 Al's Plumbing, Heating and Air Conditioning takes two pressure readings:

• The air pressure entering the system
• The air pressure leaving the system.
• We add the two pressures together for the total pressure.

Al's Plumbing. (2012, March 3). Static Pressure Testing, Ductwork Pressure Testing Al's Plumbing. Retrieved April 18, 2016, from http://alsplumbing.com/air-conditioning-and-heating/maintenance-tune-ups/static-pressure-testing/

Results:

On the Supply-Air Side (air coming out the ducts in the rooms):

• If the pressure reading is Too Low, there is air leakage in the ductwork bringing air to the rooms.
• If the Static Air-Pressure reading is Too High, there is restricted airflow in the ductwork bringing air to the rooms.

Corrections may include resealing the Supply-Air ductwork, or eliminating airflow blockages.   On the Return-Air Side (the large vents which have no shut-off lever):

• If the Static Air Pressure reading is Too LOW -- there is a disconnected return-air duct, or ductwork is too large.
• If the Static Air-Pressure reading is Too High -- there are not enough return air ducts or ductwork is too small.

Corrections may include adding more Return-Air ductwork, or increasing the size of the Return-Air duct work to increase airflow Here are photos showing Supply-Air Problems:

Unsealed pipes carrying air to rooms resulting in air leakage.

Improperly installed (compressed) ductwork resulting in an air-flow restriction.

The Goal Is Simple:

The amount of air coming out of all the rooms' ducts should be quite similar to the amount going into the return-air vents (adjusting for the airflow resistance caused by the furnace itself -- that information is provided by the furnace manufacturer) Learn how High-Merv Air Filters can dramatically reduce system air flow High MERV Filter and System Air Flow