Nc class stainless, Marley, Specifications: base – SPX Cooling Technologies SS-NC-08A User Manual

Page 5: Cooling tower

Advertising
background image

Specifications

Specification Value

Marley

/

NC Class Stainless

Cooling Tower

/

Specifications: Base

5

2.0

Thermal Performance and Efficiency:

2.1

The tower shall be capable of cooling

_____ m

3

/h of water from ____ °C to

_____ °C at a design entering air wet-

bulb temperature of _____ C and its

thermal rating shall be Certified by the

Cooling Technology Institute.

2.2

The tower shall be capable of a mini-

mum _____ m

3

/h/kilowatt efficiency per

ASHRAE Standard 90.1.

2.3

CTI Certification notwithstanding,

the cooling tower manufacturer shall

guarantee that the tower supplied

will meet the specified performance

conditions when the tower is installed

according to plan. If, because of a

suspected thermal performance defi-

ciency, the owner chooses to conduct

an on-site thermal performance test

under the supervision of a qualified,

disinterested third party in accordance

with CTI or ASME standards during the

first year of operation; and if the tower

fails to perform within the limits of

test tolerance; then the cooling tower

manufacturer will pay for the cost of

the test and will make such corrections

as are appropriate and agreeable to the

owner to compensate for the perfor-

mance deficiency.

3.0

Warranty:

3.1 The entire tower, including struc-

ture, casing, basins, decking, fan(s),

motor(s), and all mechanical drive com-

ponents (including belts, if used) shall

be warranted against failure due to

defects in materials and workmanship

for a period of five (5) years from the

date of shipment to the job. Towers not

covered by a warranty of this scope

will not be accepted.

4.0

Design Loading:

4.1

The tower structure, anchorage and all

its components shall be designed by

licensed structural engineers per the

International Building Code to with-

stand a wind load of 1.44k/Pa, as well

as a .3g seismic load. The fan deck

and hot water basin covers shall be

CTI Certification means that the tower

has been tested under operating condi-

tions and found to perform as rated by

the manufacturer under those circum-

stances. It assures the buyer that the

tower is not intentionally or inadvertent-

ly undersized by the manufacturer.

The minimum efficiency per ASHRAE

Standard 90.1 for induced draft open cooling towers applied to comfort

cooling is 8.68 kW @ 35/29.5/24. There are no efficiency requirements for

non-comfort cooling applications. If you want greater efficiency you can

require it by specifying a higher ASHRAE Standard 90.1 m

3

/h/kilowatt.

CTI certification alone is not sufficient to assure you that the tower

will perform satisfactorily in your situation. Certification is established

under relatively controlled conditions, and towers seldom operate

under such ideal circumstances. They are affected by nearby structures,

machinery, enclosures, effluent from other towers, etc. Responsible and

knowledgeable bidders will take such site-specific effects into consider-

ation in selecting the tower—but the specifier must insist by the written

specification that the designer/manufacturer guarantee this “real world”

performance. Any reluctance on the part of the bidder should cause you

some concern.

It is important to understand the distinction between structure and

anchorage. Specifying that only the anchorage meet these require-

ments means the tower can become non-functional, even fall down, yet

remain attached to the foundation. Specifying structure will require the

tower to remain operational.

The indicated design values are the minimum allowables under accept-

ed design standards. They give you assurance that the tower can be

Advertising