Recent content by xpsboy

Misterdonut, When you say estimate the pressure differential through the units coil, control valve and piping to and from the header - does it mean the Total Pump Head? If I have 30m Aq (~100 ft of water) total pump head does it mean that is my diff. pressure sensor setting? Thank you in advance.

How to find the value of Differential Pressure Transmitter that will give signal to VFD to modulate? Thanks in advance.

can you please let me know what will be my pump setpoint (psi) if I have 30mAq total head? Also the diff. press transmitter will give signal to VFD to modulate the pump water flow? or pump will modulate base on temperature difference?

Thank you sir!

Mechengnpc, So when you deduct the room pressurization to supply air, that value is the "spill air" - where you need to exhaust the spill air, at the return duct before or after the return fans? Also how's the automation control of spill air, what set point or value to work/activate the spill air?

My boss told me to consider spill air and economizer...is that make sense?

My boss told me to consider "spill air" when designing AHU...please educate me how to design spill air. Thank you in advance.

What refernce are you using for fittings equivalent lenght? Also do I consider each valves when calculating the total head? Pipe lenght, fittings, coil press drop, valves (?) --- are this the information i need when do pump head? Thank you in advance.

Anybody can help me where can I found good reference for air side economizer design and commissioning? Thank you.

Cooling Cap = density x water flow rate x delta T Or (Short cut) BTU/hr = 500 x GPM x dT 30% propylene, EAT: 10 LAT: 98.2 EWT: 170 LWT: 150 What will be the density value to get the GPM? Thank you in advance.

How to get the steam data (inlet pressure & lbs/hr) for heating coil? Thanks

Hi MechEngNpe, I browse the titus website and I look for one of vav boxes. Data are based on 180f entering water and 75f entering air. What will be the recommended delta T for air and water? Btw this is fan powered - parallel.

Thanks. Where can i found the "C" value using ASHRAE handbook?

Mechengnpce, I'm on ASHRAE fundamentals chapter 21 duct design but can't find the duct fitting equivalent lenght. Also I'm not familiar using the coefficient for duct fittings, i think i need to use smacna if i will look using the coefficient when finding the duct fittings loss?

Anybody can guide me where can I find the equivalent fitting loss for duct and pipe using ASHRAE handbook? I'm browsing my online access of ASHRAE handbook but can't find the tables for equivalent lenght. Also, when we do the total static pressure head I use % for getting the fitting pressure...