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MECHANICAL ENGINEERING FOR SYSTEM BALANCE. ASHRAE MEETING 2/15/2007 NORTHERN NEVADA CHAPTER 126 MATT BRENNAN, TBE. TRIPLE DUTY VALVES. FUNCTIONS SIZING INSTALLATION. FUNCTIONS. SHUTOFF VALVE FLOW CONTROL CHECK VALVE FLOW METERING
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MECHANICAL ENGINEERING FOR SYSTEM BALANCE ASHRAE MEETING 2/15/2007 NORTHERN NEVADA CHAPTER 126 MATT BRENNAN, TBE
TRIPLE DUTY VALVES • FUNCTIONS • SIZING • INSTALLATION
FUNCTIONS • SHUTOFF VALVE • FLOW CONTROL • CHECK VALVE • FLOW METERING • STRAIGHT PATTERN VALVE CONVERTIBLE TO A RIGHT ANGLE VALVE
SIZING! • DO NOT ASSUME THIS TO BE A LINE SIZE VALVE. • DO INCLUDE A SCHEDULE FOR TDV’s, INCLUDE VALVE Cv & GPM 100% STEM RISE.
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.
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.
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.
OPTIONS • INSTALL A FLOW VENTURI OR CIRCUIT SETTER WITH A CHECK VALVE. • VERY ACCURATE
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.
DETAILS! • SHOW PETE’S PLUGS AS THE FIRST DEVICE AT THE ENTERING AND LEAVING CONNECTIONS OF ANY HEAT EXCHANGER! IE COIL, CHILLER, HX, BOILER, etc.
DETAILS! • HAVE PETES PLUGS INSTALLED NEXT TO ALL TEMPERATURE AND PRESSURE CONTROL SENSORS FOR CALIBRATION.
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.
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.
VAV BOXES • TYPE • SCHEDULE • SIZING
SERIES FAN POWERED • FAN HANDLES ALL AIR THAT SERVES THE SPACE.
PARALELL FAN POWERED • FAN ONLY HANDLES RETURN PLENUM AIR THAT GOES TO THE SPACE.
VAV WITH REHEAT • DAMPER CONTROLS ALL AIR THAT GOES TO THE SPACE. NO FAN.
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.
SIZING! • ALWAYS START BY SELECTING BOX SIZE TO PRODUCT 2000 FPM VELOCITY ±15% AT THE BOX INLET WHEN AT MAXIMUM COOLING CFM.
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.
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.
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.
SPORTING CLAY SHOOT • ASHRAE FUNDRAISER • APRIL 15, 2007 • SAGE HILL CLAY SPORTS • 100 SPORTING CLAYS • SHOTGUN RAFFLE • BBQ LUNCH • FUN FOR ALL