ZL-30T 30 Ton Industrial FRP Counter Flow Cooling Tower - Engineering Specifications
The ZL-30T FRP counter flow cooling tower delivers 105.51 kW heat rejection at 30 refrigeration tons with 23.4 m3/h water flow rate. The following sections detail engineering specifications, operational considerations, and application-specific integration guidance for the ZL-30T.
The 30-ton ZL-30T is rated at 105.51 kW of heat rejection under CTI STD-201 design conditions (95°F inlet water, 85°F wet-bulb, 5°F range). The flow rate of 23.4 m3/h is calibrated to a 5°C temperature drop across the fill media, which is the standard range for induced-draft counter-flow cooling towers. At this flow rate, the ZL-30T delivers exactly 105.51 kW of heat rejection when the leaving water temperature reaches 32°C against a 27°C wet-bulb. For applications requiring higher temperature drops (8-10°C), the tower can accept lower flow rates while maintaining the same 105.51 kW heat duty, provided the wet-bulb approach stays within 5°C of design. This makes the ZL-30T suitable for large commercial buildings (>2000 m²), 350-500 ton injection molding, mid-to-large data centers, district cooling plants where standard HVAC loop conditions apply.
The wet-bulb approach is the most critical performance metric for any cooling tower. It represents the difference between the leaving water temperature and the ambient wet-bulb temperature. Under standard design conditions (27°C WB), the ZL-30T achieves a 5°C approach, meaning the leaving water reaches 32°C. As ambient conditions deviate from design, the approach varies predictably: at WB 24°C the leaving water drops to 29°C; at WB 30°C (hotter climate) the leaving water climbs to 35°C; at WB 21°C the leaving water drops to 26°C. The ZL-30T's 230 CMM airflow at 770 mm fan diameter is specifically sized to maintain this 5°C approach across the expected operating range. Off-design performance is documented in CTI thermal performance curves and is reproducible year-over-year when water flow and chemistry remain within design limits.
The ZL-30T uses counter-flow geometry where water falls downward through the fill media while air rises upward through the same media. This counter-flow arrangement provides 15-20% better thermal performance than cross-flow designs at the same airflow rate. The tower diameter of 1650mm and height of 2000mm are optimized for the 23.4 m3/h water flow rate: the diameter provides sufficient cross-sectional area for 230 CMM airflow to reach every part of the fill media, while the height ensures water spends adequate residence time in contact with the rising air stream. PVC film fill media is standard for low-fouling operation, with optional cellular drift eliminators reducing drift loss to 0.005% of circulating flow (less than 10 L/h for the ZL-30T).
The ZL-30T's axial fan delivers 230 CMM of airflow at design conditions, driven by a 0.75 kW motor at 380V 3-phase 50 Hz. The 770mm propeller diameter is sized to move 230 CMM against the 16 kPa external static pressure of the fill media and drift eliminators. Fan tip speed is kept below 60 m/s to minimize noise (the ZL-30T operates at 60-65 dB(A) at 5 meters) and to extend bearing life beyond 50,000 hours. Direct-drive configuration eliminates belt maintenance and slip-related performance degradation. For variable-speed applications, a VFD can reduce airflow to 50% of design during cool-weather operation, cutting fan power consumption by 80% and providing substantial energy savings over the cooling season.
The ZL-30T's 16 kPa head loss at design flow (23.4 m3/h) is the external static pressure that the chilled water pump must overcome, in addition to the chiller evaporator and piping losses. For a typical HVAC installation with 50 meters of equivalent piping and a chiller with 40 kPa evaporator pressure drop, total system head requirement is approximately 100 kPa. The ZL-30T's 16 kPa contribution is moderate, allowing standard end-suction pumps at 50 Hz operation. Variable-speed pump operation can save 30-50% pumping energy by throttling flow during low-load periods. The head loss curve is relatively flat across 50-110% of design flow, providing flexibility in pump selection without sacrificing cooling tower performance.
The ZL-30T shell is constructed from fiberglass-reinforced polyester (FRP) with UV-stabilized gelcoat surface, providing 15-20 year service life in outdoor environments. Dry weight of 116 kg and operating weight of 530 kg (when filled with water) require a flat concrete pad capable of supporting 580 kg per square meter. The ABS fan is corrosion-resistant and balanced to ISO 1940 G6.3 standard. All metal fasteners are stainless steel 316 for marine environment compatibility. Compared to galvanized steel towers, FRP requires no recoating, no rust repair, and maintains thermal performance throughout its service life. The ZL-30T's FRP construction is CE certified for European installations and IP55 rated for the electrical motor enclosure.