How 33E5021 works
33E5021 is a tank-type preheater, designed to keep the coolant at an optimal temperature before engine startup. Heating is performed directly in the cooling circuit, and the fluid moves through natural convection, without an integrated circulation pump.
The preset thermostat automatically turns heating on at 38°C and off at 49°C, maintaining a stable system temperature. By maintaining a constant thermal baseline, the unit reduces startup strain and supports reliable engine operation in low-temperature conditions.
Heating unit
Built from die-cast aluminum for corrosion resistance and efficient heat transfer in the cooling circuit.
Natural Circulation
Heating the coolant generates natural convection, without an integrated pump, for simple and reliable operation.
Temperature Control
Preset thermostat, calibrated to automatically maintain temperature within an optimal operating range.
Integrated Safety
Internal thermal protection designed to prevent overheating and ensure safe operation.
Technical specifications
Heating Unit
Housing material: die-cast aluminum
Heating element: integrated electric resistance element
Construction type: one-piece body, corrosion-resistant
Hose connection: 5/8” (15.8 mm)
Liquid Circulation
Circulation type: natural (by convection)
Integrated pump: no
Operating principle: direct heating of the fluid in the circuit
Temperature Control
Thermostat type: preset (fixed)
Temperature range: 35–50°C
Operating mode: automatic on/off switching
Safety
Protection type: integrated thermal protection
Reset mode: automatic
Compliance: CE certified
Electrical Supply
Rated power: 1000 W
Supply voltage: 230 V
Frequency: 50 / 60 Hz
ZeroStart
Simple operation • Reliable heating
ZeroStart is a range of tank-type preheaters designed to maintain coolant temperature through natural circulation. The system provides consistent engine heating and easier starts, even in low-temperature conditions.
Temperature is controlled by a preset thermostat, eliminating the need for adjustments and ensuring stable operation in service.
Power suited to the application
The power rating expressed in watts indicates the unit's heating capacity. In the ZeroStart range, values between 750 W and 2250 W are optimized for small and medium-sized engines, ensuring a constant temperature for easier starts.
Simple operation
Heating through natural circulation
The coolant is heated and set in motion by natural convection, without an integrated circulation pump.
Preset thermostat
The temperature is automatically maintained within a preset range, available in multiple operating bands.
For essential applications
ZeroStart models are intended for installations where simple construction and operational reliability are priorities.
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