The range of the certified thermal operating conditions shall not extend beyond the certified characteristics as per CTI STD-201, these being:
- Entering wet bulb temperature: - 12.8°C to 32.2°C (55°F to 90°F)
- Cooling range > 2.2°C (4°F)
- Cooling approach > 2.8°C (5°F)
- Process fluid temperature < 51.7°C (125°F)
- Barometric pressure: - 91.4 to 105.0 kPa (27" to 31" Hg)
Certification tests on cooling towers shall be conducted with the measured flow rate of the process fluid at no less than 60% or more than 140% of the midpoint of the published flow rate limits for the cooling tower model.
During the certification tests, the product shall be operating within the manufacturers recommended limits of hot water head/nozzle spray pressure.
Certification tests shall be conducted with a specific product operating within 10% of its rated fan motor output power.
Prior to evaluating the unit performance, the capacity at the test barometric pressure shall be adjusted to the standard barometric pressure using the equation below:
CSBP= Capacity adjusted to Standard Barometric Pressure
CTBP = Capacity at Test Barometric Pressure
K1 = Constant equal to .0023 for SI and 0.0078 for IP
BPStd = Standard Barometric pressure equal to 101.325 kPa for SI and 29.92 in Hg for IP
BPT = Test Barometric Pressure in kPa (in Hg)