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Item # CH24-7K, Self-Contained, Hydraulically Driven Rooftop Air Conditioning and Heating Units

The MacBone C Series Rooftop 24,000 BTU/hr air conditioning unit is an overhead mounted, unitary, or self-contained unit, with a closed, precharged refrigeration circuit, driven by a single, integral, hydraulic motor. Heating is derived from the circulation of hot engine coolant, engine oil or hydraulic oil through the unit. Heating capacity is 30,000 BTU/hr at a fluid flow rate of 1.5 GPM at 140° F. The design concept is derived from the need for an air conditioning unit for industrial applications where the unit can be quickly removed for service without involving the sealed refrigeration circuit. Cooling is provided by a thermostatically controlled automotive type compressor, using R-134A refrigerant. The condenser fan and evaporator blower share a common shaft, driven by the hydraulic motor with sufficient power to produce substantial condenser air flow, even with a filter on the outside coil, thus insuring reliable performance even in a heavily dust laden environment. Substantial power delivered to the inside air blower also assures delivery of full system capacity under all conditions. Induction of 10% outside air provides cab pressurization to exclude dust and other contaminants from entering the cab environment.

Hydraulic drive input is usually, but not necessarily, from a pump driven by the vehicle's engine and utilizing the vehicle's hydraulic reservoir. Required flow is a constant 10 GPM at a variable pressure from 600 to 1400 PSIG. System pressure relief, provided by the installer, should be set at 1650 PSI. Electrical input of 3.5 amps, at 12 or 24 VDC, is used only to activate the compressor clutch.

All units utilize non-CFC, R-134A refrigerant, measure 36 1/2 x 24 1/2 x 12 1/2 inches high and weigh 175 pounds. Hydraulic lines are #8, supply and return, up to 40 feet. The motor has an external case drain to protect its shaft seal. Four 1/2 inch SAE mounting bolts provide for quick removal for service or replacement. The dual V belt drive system has an automatic tensioner and operates in a closed, ventilated area. Recommended operating time before overhaul is 6000 hours. Recommended unit life is four overhaul cycles. Note, however, that we are finding units with up to 6000 hours in need of drive belts only. We also note that four overhaul cycles may not be the limit.
Mounting OptionsOverhead Self Contained Unitary
ColorWhite with Patriotic MacBone Logo
Length36-1/2 in 92.7 cm
Width24-1/2 in 62.2 cm
Height12-1/2 in 31.8 cm
Weight (Basic Unit)142 lb 64 kg
Weight (Unit with Sub Base)Unit with sub-base, air ducts and weather cover top - 175 lb Unit with sub-base, air ducts and weather cover top -79 kg
Cooling Capacity24,000 Btu/hr
Note (Cooling Capacity)Cooling at a unit motor speed of 2000 RPM at standard rating conditions.
Heating Capacity30,000 Btu/hr
Note (Heating Capacity)Heating with supply oil or water at 150° at 1.5 GPM.
Air FlowNominal 800 CFM delivered from the unit.
Current3.5 A
Voltage12 V 24 V
Hydraulic PumpNet pump output should be 10 GPM, 600 to 1400 PSI, constant volume, variable pressure. A dedicated pump is best. Call MacBone engineering for other possible options.
Unit MotorMotor displacement is 1.00 cubic inch/rev. and requires 10 GPM to operate at 2000 RPM. Drives compressor and fans through a dual V Belt drive, tensioned by a spring loaded idler.
Hydraulic LinesSupply and return hoses, 1/2" I.D. (#8). Case drain, 3/8" I.D. (#6).
RefrigerantR-134A, approximately 1 lb, 6 oz.
Drive Belts(2) "A" section (1/2" wide) belts, Goodyear AX46.
Speed ControlVariable; manually operated.
Heat ControlVariable; manually operated.
Cooling ControlThermostat; operator adjustable, from 60 °F to 90 °F.
Air FiltersThe inside or evaporator air filter is 10" x 18" x 1/2". The outside or condenser air filter is 11" x 20" x 1". Filters are washable and reusable or may be replaced with locally available filter material.
LubricationFan shaft bearings should be greased annually with a lithium, mineral or synthetic base grease
ServiceWeekly, air filters should be cleaned. Monthly, the speed control valve stem packing nut should be tightened if leaking. Annually, the unit should be removed for cleaning, inspection of the (4) shock mounts and duct seals, lubrication of the fan shaft bearings and belt replacement.
OverhaulFactory replacement of all wear-limited components should be considered after 6000 hours of operating time.
MaterialsAll sheet metal parts, except for the stainless steel weather top cover, are galvanized steel with exterior surfaces polymer powder-coated. All fasteners are grade 5 plated steel with self-locking nuts. Coils are copper tubes with aluminum fins. Refrigerant and heating fluid lines are copper with sleeved and flared or silver soldered joints. Hydraulic lines are steel, SAE 100R2 type, with a 4,000 PSI working pressure and a 16,000 PSI burst pressure.
Shipping Length46 in
Shipping Width42 in
Shipping Height16 in
Shipping Weight200 lb