Lifebreath CAF-02-MB installation manual Pitot Tube and Gauge, Placement of the Pitot Tube

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Pitot Tube and Gauge

Figure A

Placement of the Pitot Tube

Pitot Tube

Note: For best results keep Pitot tube

well away from dampers.

Figure B

This is an example for determining the airflow in a 6" duct. The Pitot tube reading was 0.025 inches of water. From the chart, this is 640 feet per minute.

The 6" duct has a cross sectional area of:

=[3.14 x (6"÷12)2]÷4

=0.2 square feet

The airflow is then:

640 ft./min. x 0.2 square feet = 128 cfm

For your convenience, the cross sectional area of some common round duct is listed below:

DUCT DIAM. (inches) CROSS SECTION AREA (sq. ft.)

	5.0	.14
	6.0	.20
	7.0	.27
		INSULATED PIPE
		WITH VAPOUR
	BUILT-IN	BARRIER
	BUILT-IN
	BALANCING	OUTSIDE
	DAMPERS	OUTSIDE
	DAMPERS	HOOD
		HOOD
		BACK DRAFT
		DAMPER
		Figure C

The accuracy of the airflow reading will be affected by how close to any elbows or bends the readings are taken. Accuracy can be increased by

taking an average of multiple readings as outlined in the literature supplied with the Pitot tube.

Balancing Collar Instructions

Push and turn with slotted screwdriver. Damper automatically locks when pressure is released.

Insulated flexible

ducting

When connecting ductwork to the collar, take note where screws are located. Screws should be located no further than 1/2” from outside edge of collar, so as not to impede operation of the damper.

1/2”

Figure D

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Image 26

Contents OPERATION, Sizing and Installation Manual Table of Contents Introduction HRV Aluminum CoreDescription and Purpose Important NoteCombo System Basic Principles Closed/Open Combo SystemAir System Call for Space Heating Only OperationCall for Domestic Hot Water and Space Heating Operation Water PipingManual Valves Throttling Valve Shut Off ValvesDrain Valve Check ValvesCold Off Season Circulation TimerExpansion Tanks WaterWater Heater Thermostat Air Handler Return Air TemperatureAir Handler Temperature Rise Room ThermostatHead Pressure Design vs. Field ConditionsWater System Pressures Flow RateModel Number Nomenclature Breakdown Warranty Specifications Model CAF-U-S4A-24-P16Dimensions & Clearances Core Filters CaseSpecifications Model CAF-U-L4A-36-P16 CAF-U-L4A-36-P16CAF-D-S4A-24-P16 Specifications Model CAF-D-S4A-24-P16Filters Case Specifications Model CAF-D-L4A-36-P16 CAF-D-L4A-36-P160302 Specifications Model CAF-H-S4A-24-P16CAF-H-S4A-24-P16 Specifications Model CAF-H-L4A-36-P16 CAF-H-L4A-36-P16Specifications Model CAF-U-L2A-48-P16 CAF-U-L2A-48-P160211 Specifications Model CAF-U-00-36-P16CAF-U-00-36-P16 0209 Specifications Model CAF-U-00-48-P16CAF-U-00-48-P16 Duct Connections InstallationLocating The Unit Option 1 Ventilation Ports Off Left SideOption 2 Ventilation Ports Off Right Side DuctingOutside Ducting the Weatherhoods Locating Intake WeatherhoodLocating the Exhaust Weatherhoods Locating WeatherhoodPrior to balancing, ensure that Balancing ProcedurePitot Tube Air Flow Balancing Balancing Collar Instructions Placement of the Pitot TubePitot Tube and Gauge Piping HRV Drain Line DiagramDrain Line Plumbing Water HeaterSelecting Different Heat & Cool Speeds Automatic Self TestBasic Functions ECM Motor Settings Heating/Cooling Off Season Circulation TimerOperation VentilationStart-Up Procedure Following conditions must be met prior to start-upTroubleshooting Humidity levels are too low Humidity levels are too highWater Pump Performance Specifications System CommissioningPage Page Page Page Page Page Diagram ECM CAF/Air Handler Wiring Diagram Fan Motor