A compressor crankcase heater warms the oil-containing region of a refrigeration or air-conditioning compressor.
A compressor crankcase heater warms the oil-containing region of a refrigeration or air-conditioning compressor. This can reduce the tendency for refrigerant to migrate into cooler compressor oil during off periods. The required heater and operating sequence depend on the compressor and refrigeration system. An external heating band is selected around the specified shell location, circumference and electrical duty. It is a compressor accessory with a defined operating purpose; it does not correct liquid refrigerant floodback, poor system control or an unrelated mechanical fault.
The aim is controlled warming for off-cycle refrigerant migration management, with the correct fit, power and control relationship. A replacement enquiry should begin with the compressor model and existing heater information.
A band around the designated compressor shell area provides external heat input. Selection must match the shell dimensions, fastening arrangement, available mounting space and the compressor manufacturer's heater requirements.
Enquire about this configurationUse the actual mounting location and available access to define band fit and the fastening envelope.
Compare heater voltage and power with the approved equipment requirement, including the way the heater circuit is controlled.
Review the lead exit and termination against service panels, vibration-prone locations and the original cable route.
Include the old heater label, compressor identification and photographs of the installed position to support an unambiguous comparison.
Share these details with your inquiry. Product ratings and operating limits are confirmed for the selected configuration.
| What to specify | Unit / format | Selection guidance |
|---|---|---|
| Compressor identification | model / drawing | Provide the exact compressor model, application and relevant heater or installation instructions. |
| Shell fit | mm | Give the mounting diameter or circumference, permitted band position and any obstruction around the shell. |
| Band envelope | mm | State the required heated length, width and fastening clearance; include a drawing for replacement matching. |
| Heater power | W | Use the compressor manufacturer's heater requirement or an approved engineering specification, rather than selecting by size alone. |
| Supply characteristics | V / Hz / AC or DC | Confirm the actual heater supply and control-circuit arrangement independently of the compressor motor nameplate. |
| Ambient and off-cycle duty | °C / operating schedule | Describe minimum ambient conditions, wind exposure and expected stopped periods for the equipment. |
| Leads and termination | mm / connector | Identify lead length, exit direction, connector interface and routing constraints inside the equipment. |
| Control requirements | sequence | Provide the intended control and pre-start requirements from the compressor or equipment manufacturer. |
Provide the exact compressor model, application and relevant heater or installation instructions.
Give the mounting diameter or circumference, permitted band position and any obstruction around the shell.
State the required heated length, width and fastening clearance; include a drawing for replacement matching.
Use the compressor manufacturer's heater requirement or an approved engineering specification, rather than selecting by size alone.
Confirm the actual heater supply and control-circuit arrangement independently of the compressor motor nameplate.
Describe minimum ambient conditions, wind exposure and expected stopped periods for the equipment.
Identify lead length, exit direction, connector interface and routing constraints inside the equipment.
Provide the intended control and pre-start requirements from the compressor or equipment manufacturer.
A correctly specified crankcase heater supports the compressor's off-cycle protection strategy. Selection remains tied to the compressor model, refrigeration application and manufacturer-defined operating requirements.
External bands may form part of an equipment design where the compressor requires crankcase heating. The accessory must be coordinated with the unit's controls and service access.
Replacement work requires a match to the original duty and dimensions. Identifying only the band diameter leaves important electrical, environmental and control requirements unresolved.
Find the heater requirement for the exact compressor and application. Record the specified power, control sequence and any required warming before compressor operation.
Measure the designated location and document obstructions, lead direction and fastening space. A band that fits somewhere on the shell may still be incorrectly positioned for the intended duty.
Compare the electrical supply, control arrangement and service environment. Have the finished selection reviewed with the equipment requirements before treating it as an approved replacement.
Send your application details, drawing and planned quantity. We can review the configuration and the information needed for a quotation.
These references explain heating principles. Confirm the ratings, approvals and operating limits of the proposed VELHEAT configuration in its own documentation.
Off-cycle refrigerant migration purpose, limits on excessive heater power, and distinction from floodback or slugging protection.
