Open Expansion Tank Location

[tmartin125]

I am designing a closed loop cooling system for multiple consumers at varying heights above baseline. The system will include a vented (open top) expansion tank to account for fluid expansion due to temperature differentials. The bottom of the expansion tank will connect to the suction side of the pump. Also several vents will be connected between the top (air side) of the expansion tank and various high points in the system. Is it sufficient to locate the expansion tank simply at the highest point of the system or is there a minimum height that has to be met (calculated) in order to prevent media from coming out the top of the expansion tank vent? Is there a design standard or guideline for design of open expansion tanks that can provide direction? Your comments are appreciated. Thanks.

 

[BigInch]

Highest, highest point.
There is no apparent reason that the bottom of the tank must be connected to pump.

you must get smarter than the software you're using.

 

[tmartin125]

The expansion tank is connected to the pump suction in order to create a point of zero pressure, or at least near zero pressure.
I thought there would be a requirement for the expansion tank to be a certain distance above the highest point of the system but haven't been able to find this requirement in reference material.. maybe it does not exist.

 

[tmartin125]

Looks like Mark's Mechanical Engineers Handbook says open expansion tanks should be located at least 3 feet from the highest point radiator or main.

 

[BigInch]

In a closed loop system, all points are connected to pump suction.

you must get smarter than the software you're using.

 

[bimr]

This system would have to have it expansion tank at the highest point because the expansion tank open to atmosphere. Having said that, you must not be working with much pressure, otherwise your tank would have to be very high.

http://www.paceplumbing.co.uk/central-heating/types-of-heating-system.html

You can also use a tall tank.

http://www.engineeringtoolbox.com/expansion-tanks-d_885.html