MECHANICAL ENGINEERING FOR SYSTEM BALANCE

1
MECHANICAL ENGINEERING FOR SYSTEM BALANCE

• ASHRAE MEETING 2/15/2007 NORTHERN NEVADA CHAPTER
  126
• MATT BRENNAN, TBE

2
TRIPLE DUTY VALVES

• FUNCTIONS
• SIZING
• INSTALLATION

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FUNCTIONS

• SHUTOFF VALVE
• FLOW CONTROL
• CHECK VALVE
• FLOW METERING
• STRAIGHT PATTERN VALVE CONVERTIBLE TO A RIGHT
  ANGLE VALVE

4
SIZING!

• DO NOT ASSUME THIS TO BE A LINE SIZE VALVE.
• DO INCLUDE A SCHEDULE FOR TDVs, INCLUDE VALVE Cv
  GPM 100 STEM RISE.

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SIZING!
6
SIZING!

• AHSRAE 90.1 RECOMMENDS, IF THIS IS THE PRIMARY
  SYSTEM VALVE AND IS SET LOWER THAN 50 STEM RISE
  THAT THE IMPELLER BE TRIMMED TO THE NECESSARY
  DESIGN FLOW. THIS WILL REDUCE ELECTRICAL ENERGY
  CONSUMPION AND COMPLY WITH THE NATIONAL ENERGY
  BUILDING CODE STANDARD.

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SIZING!

• MOST MANUFACTURES REQUIRE A MINIMUM STEM RISE OF
  50 WITH A MINIMUM READING OF 3 FEET OF PRESSURE
  DROP AND MOST HAVE A MAXIMUM OF 25 FEET OF
  PRESSURE DROP.

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INSTALLATION

• DETAILS---DETAILS---DETAILS
• INCLUDE IN YOUR DETAIL SECTION A DETAIL THAT
  SHOWS THE TRIPLE DUTY VALVE INSTALLED AT A
  MINIMUM OF 5 PIPE DIAMETERS IN THE STAIGHT DOWN
  STREAM AND UPSTREAM OF THE VALVE. INCLUDE TEXT TO
  COMPLY WITH VALVE MANUFACTURES INSTALLATION
  RECOMMENDATIONS.

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DETAILS!
10
DETAILS!
11
DETAILS!GAUGE MANIFOLD
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OPTIONS

• INSTALL A FLOW VENTURI OR CIRCUIT SETTER WITH A
  CHECK VALVE.
• VERY ACCURATE

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OPTIONS

• WHEN USING VARIABLE PUMPING VIA TRANSDUCER AND
  VFD, DO NOT REQUIRE A TDV, ALL THAT IS NEEDED IS
  A CHECK VALVE AND ISOLATION VALVE.

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DETAILS!

• SHOW PETES PLUGS AS THE FIRST DEVICE AT THE
  ENTERING AND LEAVING CONNECTIONS OF ANY HEAT
  EXCHANGER! IE COIL, CHILLER, HX, BOILER, etc.

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DETAILS!

• HAVE PETES PLUGS INSTALLED NEXT TO ALL
  TEMPERATURE AND PRESSURE CONTROL SENSORS FOR
  CALIBRATION.

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CIRCUIT SETTERS
17
SIZING!

• DO NOT ASSUME THAT THIS IS TO BE A LINE SIZE
  DEVICE.
• IN MOST CASES ON SMALLER COILS (REHEAT), LINE
  SIZE IS TOO LARGE.

18
SIZING!
19
INSTALLATION

• HAVE DETAIL SECTION SHOW THE CORRECT AMOUNT OF
  STRAIGHT PIPE DIAMETERS BEFORE AND AFTER THE
  BALANCE VALVE.
• INCLUDE A NOTE TO COMPLY WITH THE BALANCE VALVE
  MANUFACTURES RECOMMENDATIONS.

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INSTALLATION
21
INSTALLATION
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VAV BOXES

• TYPE
• SCHEDULE
• SIZING

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SERIES FAN POWERED

• FAN HANDLES ALL AIR THAT SERVES THE SPACE.

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PARALELL FAN POWERED

• FAN ONLY HANDLES RETURN PLENUM AIR THAT GOES TO
  THE SPACE.

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VAV WITH REHEAT

• DAMPER CONTROLS ALL AIR THAT GOES TO THE SPACE.
  NO FAN.

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SCHEDULE

• NUMBER EACH VAV WITH ITS OWN TAG NUMBER.
• DO NOT SELECT 6 OR 7 TERMINALS AND SCHEDULE THEM
  WITH GENERAL INFORMATION.
• INCLUDE SPECIFICALLY PRIMARY AIR MAXIMUM,
  MINIMUM, REHEAT AND FAN CFM.
• INCLUDE AREA SERVED AND ROOM s.

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SCHEDULE
28
SIZING!

• ALWAYS START BY SELECTING BOX SIZE TO PRODUCT
  2000 FPM VELOCITY 15 AT THE BOX INLET WHEN AT
  MAXIMUM COOLING CFM.

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SIZING!

• THIS WILL MAKE THE BOX MORE CONTROLABLE AT THE
  MINIMUM SET POINT AS MOST BOX GRAPHS AND
  CONTROLERS CANNOT CONTROL BELOW 0.03 IN. WC.
  PRESSURE DROP. IT WILL ALSO MAKE THE BOX MORE
  ACCURATE AT BOTH ENDS.

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SIZING!
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SIZING!

• AN OVERSIZED BOX WILL CAUSE THE CONTROLER TO BE
  UNCALIBRATABLE AT THE MINIMUM CFM SET POINT AS
  WELL AS CAUSE FLOW HUNTING AND POOR HEAT TRANSFER.

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SIZING!

• AN UNDERSIZED BOX WILL REQUIRE THE SUPPLY DUCT
  STATIC PRESSURE SET POINT TO BE RAISE TO A LEVEL
  THAT CONSUMES MORE ENERGY THAN NECESSARY.

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SPORTING CLAY SHOOT

• ASHRAE FUNDRAISER
• APRIL 15, 2007
• SAGE HILL CLAY SPORTS
• 100 SPORTING CLAYS
• SHOTGUN RAFFLE
• BBQ LUNCH
• FUN FOR ALL