Dwyer DAFA Manual

Page 1

Model DAFA Air Flow Indicator and Alarm

FACTORY VANE

Specications - Installation and Operating Instructions

Bulletin AQ-DAFA

The Model DAFA Air Flow Indicator and Alarm alerts users of low or no air ow conditions in pipes utilizing a thin, eld trimmable vane to sense the air ow rate. An 85 dB audible buzzer alternates with a bright red LED to alert users when the air ow rate drops, indicating low or no ow in the pipe. The DAFA is battery powered to provide versatility for where it can be installed, and offers a yellow LED to indicate a low battery. This device is ideal for monitoring radon mitigation systems by detecting a loss of air ow in the pipe and providing a signal to homeowners if the fan has stopped operating.

MOUNTING

Step 1: Drill a 3/4˝ hole in the system pipe Step 2: Clean the area of the pipe where the air ow monitor will be mounted. Step 3: If necessary, trim the vane as seen in Figure 1 for a 3˝ pipe. Step 4: Attach the vane to the body of the air ow indicator and alarm. Step 5: Peel the protective covering from the gasket. Step 6: Slide the vane through the 3/4˝ hole in the pipe and seal the gasket to the pipe. Step 7: Install the battery following the instructions in the Battery Replacement section of the manual.

NOTICE

changes in the actuation / deactuation points.

The ow switch has been designed to work in vertical pipes with the ow traveling upwards. Other congurations can lead to

5-1/8 [130.00]

1-15/32

[37.47]

3/4 [19.05] 3-33/64

SPECIFICATIONS Service: Clean air. Actuation Point: 15 CFM (4˝ pipe); 10 CFM (3˝ pipe) on decrease in ow. Audible Alarm: At least 85 dB @ 1 foot distance. Visual Alarm: Red LED for no ow alarm; Yellow LED for low battery. Wetted Materials: ABS, polycarbonate, rare earth magnet. Power Requirements: 3 V CR2450 lithium battery, included, user replaceable. Battery Life: 5 years steady state; 48 hours during alarm state. Temperature Limits: 32 to 122°F (0 to 50°C). Mounting Orientation: Vertical. Weight: 4 oz (113.4 g). Agency Approvals: CE.

ALARM POINT

Visual and audible alarm cycle activates on decrease in ow at the points noted in Table 1.

Table 1: Alarm Points Pipe Size Alarm Point

3˝ 4˝

10 CFM 15 CFM

[89.32]

2-3/32 [53.00]

4˝ PIPE INSTALLATION

Figure 1: Trimming Vane for 3˝ Pipe

3˝ PIPE INSTALLATION

TRIM ALONG INDENTATIONS IN VA

DWYER INSTRUMENTS, LLC

P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.

Phone: 219/879-8000

Fax: 219/872-9057

www.dwyer-inst.com

e-mail: info@dwyermail.com

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OPERATION

LOW/NO FLOW

The DAFA Air Flow Indicator and Alarm detects the air ow in a pipe by sensing the position of the vane. When the fan is operating normally, the ow will lift the vane in the upward position as depicted in Figure 2. As the air ow rate decreases the vane will drop down as depicted in Figure 3. If the air ow rate drops below 15 CFM in a 4˝ pipe (10 CFM in a 3˝ pipe), the red LED on the front of the device will illuminate to give a visual alert. If the ow does not regain within 30 s, the red LED will turn off and the audible alarm will sound for 10 s. The visual and audible indicators will alternate in this same pattern until air ow is regained or the battery is removed/drained.

LARM INDICATORS = OFF

AIR FLOW

Figure 2: Vane Position Under Normal Flow Conditions

AUDIBLE INDICATORS

No Air Flow: Off for 30 s; beeping for 10 s. Low Battery: Chirp every 5 minutes

LED INDICATORS

No Air Flow: Solid red LED for 30 s; off for 10 s. Low Battery: Flashing yellow LED.

TROUBLESHOOTING

• If fan appears to be operating and the DAFA Air Flow Indicator and Alarm is in the alarm state, check to see if the vane was installed properly. The vane should be able to travel in the direction of the air ow arrow.

• Next verify that there is no debris, moisture, or dust built up on the vane.

• Then check to see if the vane is hitting the wall of the pipe. If so, the vane may need to be trimmed.

BATTERY REPLACEMENT

When the battery is low, a yellow warning LED will begin to ash and an audible alarm will sound every 5 minutes to alert that it is time to replace the battery. Using a large at head screw driver, turn the battery cover 1/4 turn in the direction of the arrows on the cover. Remove the battery cover by lifting it up. Remove the coin cell battery from its compartment. Insert a new 3 V CR2450 coin cell lithium battery in the compartment with the positive (+) side of the battery facing up. Replace the cover and twist the cover using the large at head screw driver in the opposite direction of the arrows.

MAINTENANCE/REPAIR

Upon nal installation of the Model DAFA, no routine maintenance is required. The Model DAFA is not eld serviceable and is not possible to repair the unit. Field repair should not be attempted and may void warranty.

WARRANTY/RETURN

Refer to “Terms and Conditions of Sale” in our catalog and on our website. Contact customer service to receive a Return Goods Authorization number before shipping the product back for repair. Be sure to include a brief description of the problem plus any additional application notes.

LARM INDICATORS = ON

Figure 3: Vane Position Under No Flow/Alarm Condition