Cooling Tower Capacity cross checking

[pramodsale]

Can Any body tell in simple way - How to cross check the actual tonnage of a cooling tower installed already ?

 

[KiwiMace]

Which brings up a good point: I would like to know why it is that cooling tower manufacturers seem to have a special entitlement not to nameplate their equipment.

Using the model number, you can estimate the performance from the manufacturers performance specs, assuming you know or can assume CWS&R temps (often typical), local design wetbulb (refer ASHRAE tabulated by location), and flowrate (from pump).

There are lots of other factors which can throw a tower off-standard spec but this should get you ballpark.
You are far better off looking at drawings for schedules, or calling the local rep with the serial number.

 

[SAK9]

Cooling tower capacity=the tower mass flow ratexTemperature difference across the towerxspecific heat of water(based on actual measurements)

Measure the local wet bulb temperature and refer to the Tower performance charts to obtain rated capacity.

The variation between the two values should not be more than 5%(Not sure about this better check CTI stds)

Cooling tower capacity is a function of local wet bulb temperaure and therefore capacity is not mentioned on the name plate.

 

[KiwiMace]

Yes, but one might think that the design wetbulb would be a nugget of information suitable enough for the nameplate. The nameplate shows rated performance data rather than current operating conditions.

Cooling towers so rarely operate at the rated conditions, taking measurements is nothing more than spot check. A year or two of trending is a different story.

 

[chicopee]

I am uploading a JPEG attachment of an example from one of my references "Mechanical Engineering License Review " by Pefley and Newnan. This example will help you in your evaluation for cooling capacity.
Remember though what KiwiMace is saying about rated conditions.