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The principle of heat pipe in Fresh Air Handling unit is as follow:

1- The fresh air goes through the first heat pipe coil and heats up the liquid inside the coil thus the fresh air losses some of...

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1099: correct you have to count the return. It a loop.

Ashisskg: No, only one unit will be added to the friction, the unit that is in the longest loop

Ashnotcon: Transformer heat...

It is not recommended to let copper get contact with steel in the presence electrosyis such as water because it will cause galvanic corrosion.

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Standard A.C. unit operated to satisfy sensible load as it is controllled by a sensible controlling device "thermostat" and it doesnot precisely controlled humidity inside the space. Therefore in...

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Quatum

The distance between two pumps relates to the maintanance space required. From experience I can tell you that the distance should be minimum 150% the width of the pump


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Hello Rodbutler

I like technical discussions and exchange of thoughts

Here what I think

1- I know for certain that there was improvement in the functioning of balancing valves, I remmeber...

The two sizing parameters required for a pump are

1- Water Flow : this is the same as the chiller water flow. So if you have a chiller selection it will show water flow in gpm, use it for the pump...

Here are the answers to your questions

For pipes that are less than 2" use water velocity inside pipe between 2 & 4 feet per second

for pipes larger than 2", size the pipes in accordance to...

He Gopikn



a- For High Storey Building: Assuming 2 door opening.

Area of open door ( A ) = 2 x 0.9 = 1.8 m2

Egrees velocity ( Ve...

The rules state the distance between valves and fittings should be between 2 to 10 the diameter of the pipe depending in the type of upstream and downstream pipes. However, I rarely seem this...

The main components of the system are

Option 1

1- Feed up line from municipality that connect to a water meter in the premises owner property

2- The feed up line fills up a low level water...

The concept of backdrop manhole is as below;

When there is a branch connection to manhole higher than it's invert level, a backdrop is used in a manhole where the branch is thows the fluid to a...

The pressure of 3000 psi you are referring to is a result of the weight of liquid column, so the hydrostatic pressure will be equal to that pressure plus the atmosheric pressure.

Hydrostatic...

Because the standard is measured in the lab at a certain temperature such as 25 degree Celcuis. So if the temperature is different, then you use correction factors to obtain the correct value.
...

You will get better luck if you post this question in an Electrical Engineering Question Board.


This question is not for Mechanical engineers:cool:

Hello All

HVAC means Heating, Ventilation, Air Conditioning

To select AHU or FCU the least parameters required are

Option 1
Tmbh, smbh, air on coil conditions, air flow, external static...

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This is very tall order. There is not enough space in here to explain all the things involved. You need to read many NFPA codes.

In simple terms the distance between stand pipe should be maximum...

tmbh
t = Total Load
mbh = 1000 btu/hr

smbh
s = Sensible Load
mbh = 1000 btu/hr

The supplier will size the unit for you, and they have the software for it. You have to give him the sizing parameters such as

1- maximum pressure in the system.
2- maximum temperature in the...

As per ASHRAE Cavitation is the creation of vapor pockets or flashing of water into vapor.

It happens when the fluid press inside the pump falls below the operating vapor pressure. The fluid...

3-way valve is installed in the return. The mixing type is usually used with 2 inlets and one outlet.

Operation as follow; as the space become more satisfied, the bypass part of the 3-way valve...

1- Inlet line: gate valve, Double requlating valve or commissioning set or constant flow valve, Motorized butterfly.
Outlet line: basket strainer, gate valve

2- The supplier will calculate...

The way to calculate pump heat:

In closed system: you add the pressure losses due to piping and all accessories with the piping such as elbows, valves, strainers etc. plus the pressure losses due...

AS per NFPA and most regional regulation, you CAN use one pump for sprinklers, stand pipe, hydrant and hose reel

On coil is the temperatures of air at it comes to coil (just upstream of coil) it is normally between 72 to 85 FDB & 67 to 72 FWB

Air off coil is the temperatures of air after being conditioed by...

There are three types of VAV boxes

1- Bypass type:
The simplest. Inside the BOX there is a damper which modully divert the air to supply air diffusers and to return air plenum. AHU should...

Solenoid Valve is connected to the thermostat. It is an on / off valvve. If the system is satisfied, it will prevent the passage of refrigerant to the expansion valve.

Humidity is moisure in the air. Relative Humidity is the amount of moisture in the air as a percentage of what the air at that temperature and pressure can hold as maximum amount of moisture.
...

Dear friend

The answer is 100%

It seems you are confused about where diversity factor is used.

I will give an example

Assume that the project gross tonnage is 1000 tons. And due to...

What is SOL for Fraud.

It has been 16 year.

I have came across a system that uses UVC light from a special bulb that is located inside an air conditioning unit. This system ultimate purpose is to get red of mold inside the air conditioning...

Around 16 years ago, I needed to leave the country to settle a situation overseas, and I needed cash to do so. Thus I had withdrawn money from my credit card and I was not able to pay it. Also, I did...