Hydac ELH 4 1.5 H14 S Hydraulic Fan Cooler, 16 to 40 hp

A hydraulic fan drive oil cooler for machines without a spare electrical supply

The Hydac ELH 4 1.5 H14 S (HYDAC catalogue item 2592637) is a size 4 air cooled oil cooler whose fan is turned by a 14 cc hydraulic motor. Because the fan runs from the machine hydraulics, it suits mobile equipment, offshore, agricultural, construction, forestry and material handling duties where electrical power is limited. HYDAC states that the hydraulic motor drive offers more cooling in a smaller package.

The catalogue gives a heat removal range of 16 to 40 hp and oil flows of 7 to 66 gpm, with the aluminum brazed bar-and-plate core held in a welded steel housing and a plastic fan.

Technical specifications

Understanding the code

ELH 4 1.5 H14 S: ELH is the air cooled oil cooler with hydraulic fan drive, 4 the size (sizes 4, 5, 6, 8 and 9 exist), 1.5 the version number as printed, H14 the 14 cc per revolution motor and S suction airflow through the heat exchanger. Options added to the full code in the datasheet include IBT, an internal thermostatic bypass valve opening at 45 or 50 °C, and IBP, an internal pressure bypass valve, but none is part of this part number.

Sizing and operating notes

The cooler is intended for mineral oil to DIN 51524 parts 1 and 2 with filtration to ISO 4406 code 19/16, and the datasheet says to contact the supplier for other fluids. Motor drain pressure should not exceed 29 psi, and the motor fluid viscosity range runs from 10 to 600 cSt, with 30 to 45 cSt recommended. Size 4 and 5 units place the ports towards the back to cut down on fittings, and every unit has a built-in thermostat port. Heat dissipation in the datasheet is stated at a 72 °F (40 °C) difference between oil inlet and air inlet with a 5 % tolerance, so give the supplier your own temperature figures.

Plan a clean, filtered return line from the motor to the tank because the fan motor is the most pressure-sensitive part, and arrange for the oil to reach the required fan speed at your normal operating pressure. The datasheet quotes up to 125 hp cooling capacity across the range and flows up to 80 gpm, with larger flows on request, so check that size 4 is right for your duty.

Documents and quotation

The ELH datasheet is attached. Please state the oil flow, target temperature and hydraulic supply for the fan motor. See also our oil coolers and cooling systems range.

How the ELH 4 1.5 H14 S cooler works

Hot return oil from the hydraulic system flows through the brazed aluminium bar-and-plate core of the ELH 4 1.5 H14 S. A separate hydraulic supply drives the 14 cc/rev gear motor, which turns the plastic fan. In the suction (S) layout the fan pulls ambient air through the heat exchanger fins and blows it out through the fan side, so heat moves from the oil, through the core, into the air stream. The fan speed depends on the oil flow sent to the motor: at 1500 rpm the 14 cc motor needs about 5.7 gpm and at least 435 psi.

Because the fan speed comes from the oil flow, the fan can be controlled hydraulically, for example with a flow control or a variable pump, without any electrical wiring. That makes the design popular on mobile machines and in hazardous or remote locations. Each unit has a built-in thermostat port, and on size 4 the oil ports face the back of the unit to reduce the number of fittings.

ELH size 4 drawing data and motor options

Other size 4 drawing values are dimension B = 500 mm (19.69") and C = 450 mm (17.72"), cooler inlet and outlet SAE-16, motor ports SAE-10, motor drain SAE-4 and a plugged 1/2" NPT port. The housing is welded steel. The motor has an aluminium housing with steel gears and shaft. The unit can be mounted in any position. HYDAC advises requesting a certified print for critical dimensions.

Selection & ordering guide

• Size: 4, 5, 6, 8 or 9. In the datasheet chart, the bigger cores reach up to about 125 hp heat dissipation.
• Motor: H6.3, H14 (as here) or H22. A smaller motor needs less flow but more pressure for the same fan speed.
• Air flow: S = suction.
• Accessories: IBT internal thermostatic bypass (opens at 45 °C or 50 °C) or IBP internal pressure bypass, each with a 2 bar or 3 bar opening pressure drop. The ELH 4 1.5 H14 S as listed has no internal bypass.

HYDAC rates the ELH coolers at a 72 °F (40 °C) entering temperature difference (ETD) between hot oil inlet and air inlet. Industrial coolers are rated at 40 °F ETD, so when you compare ratings, scale the horsepower by the ratio of the ETDs. For a correct selection, our team needs the oil flow, the heat load and the maximum ambient temperature.

Installation & maintenance

• Leave free space on the air inlet and exhaust sides so that hot air is not recirculated.
• Pipe the motor drain directly to the tank; drain pressure must stay below 29 psi (2 bar).
• Keep the cooler circuit below 230 psi (16 bar). If cold-start pressure peaks are likely, consider a version with a bypass.
• Keep the motor oil clean to ISO 4406 19/16 and within 10–600 cSt, ideally 30–45 cSt, at no more than 90 °C.
• Clean the fins regularly with low-pressure air or water. Dust and sand on the core are the most common cause of lost cooling performance.

Typical applications in Oman & the GCC

HYDAC lists agricultural, offshore, construction, railway, industrial, utility, material handling and forestry applications. In the Gulf climate, where ambient air can exceed 45 °C, a hydraulically driven cooler like the ELH 4 1.5 H14 S is used on mobile cranes, drilling and service rigs, waste and municipal vehicles and port handling equipment. On these machines, a hydraulic fan is simpler than adding electrical power, and a sizing check at your maximum ambient temperature is essential.

Why source from Seven Star LLC

Seven Star LLC supplies HYDAC air-oil coolers and cooling system components across Oman and the GCC. Share your heat load, oil flow and ambient conditions, and our team can help confirm the correct ordering code for the ELH 4 1.5 H14 S or an alternative size. Request a quote today.