Using A Duct Blaster:

Duct blasters measure the exact amount of air leakage in a duct system. There are two types of duct systems. Metal ducts are rigid and installed with the help of a metal strip. You need to cut the joists in which ducts are installed. This strip is wrapped around the ducts. It is then coiled into the joists. Elbow joints help rigid ducts change their direction at right angle. Flexible ducts are round tubing. They have a layer of insulation. It is flexible enough to bend around a corner.

A duct blaster consists of a calibrated fan which can blow up to 1500 cubic feet/ minute of air. It has a pressure tap along with a flexible ducting to hook-up with a duct system. Duct Blasters can be installed by following below simple steps.

Connect the duct blaster to the duct system at air handler or a central return grille.

Seal all other entry points.

Turn on the fan. Increase the flow until duct system is pressurized to specified test pressure.

Use airflow and pressure gauge to measure the leakage rate. You can inject theatrical fog into duct system. This will locate the leakage spots. The duct blaster precisely measures leakiness from 20-1500 CFM.

Installing A Blower Door:

Blower doors help in energy conservation and ensure air quality. A blower door should be set up on the main door of the house and must be shielded from the wind. It can be installed by following below simple steps.

The blower door frame should be expanded. Fit in into door jamb and tighten the knobs. Remove the door frame and attach nylon cover. Connect the exterior house pressure hose in the opposite direction of the fan flow. Then install door frame in the door jamb and lock it into the jamb.

Install fan in a depressurizing direction. It should be inserted into the elastic seal around the door's cover hole. Set up gauges by attaching the gauge clamp to the door jamb. Attach gauges to the gauge clamp. Connect pressure tubing to the gauges.

Now connect interior house pressure hose between the nylon door panel and the house pressure gauge. Make sure the exterior pressure hose is not exposed to the fan flow.

Plug in all the electrical plugging. Bring the pressure gauges to zero. Turn on the fan. Run power up a few times until gauges come to a steady zero.

Blower door will calculate the air tightness in the form of air flow and leakage area. Determining air tightness of a building is important to increase energy conservation and decrease indoor pollution.

 

Source:   nylon hose ,  stainless steel hose

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