Danfoss Commercial Compressor Crankcase Heater

Technical Specifications

• Insulation resistance: minimum 100 megohms - 2500 Volts.
• Tolerance: output ±10%.
• Cold tail: 3xAWG20 or AXG18 or AVLV2/8, PVC or Silicone insulated.
• Cold tail length: 0.41~1.27 meter.
• IP55: Marking UL (cUL on 75W and on ref. 120Z0890 up to 120Z0895), CE and UKCA (except 24V).
• Admissible operating temperature: -40°C/105°C.

Introduction

These instructions pertain to crankcase heaters used for A/C and refrigeration with Danfoss Commercial Compressors. They provide necessary information regarding safety features and proper handling of this product.

Product Table

Safety Measures Prior to Assembly

• These heaters have been designed and qualified to be used with Danfoss Commercial Compressors; use with any other application is not allowed.
• Installation and servicing are to be performed by qualified personnel in compliance with all pertinent practices and safety procedures.
• Check that the heater model corresponds to the compressor model (refer to table above).
• Verify that the power supply corresponds to the heater characteristics written on the heater cable.

Assembly

• Install the heater at the lower part of the compressor where the oil is accumulated (below the sight glass) as shown in Figures 1, 2, 3 & 4. Fix over the Ebox.
• Fit the crankcase heater around the compressor and ensure good contact along the entire length.
• Lock the clip and tighten the screw (see Fig. 5) Max torque 2 Nm.
• Before performing an electrical connection, ensure the main power supply has been switched off and isolated.
• A separate permanent electrical supply is recommended.
• Belt crankcase heaters are not self-regulating; control must be applied to energize the belt heater once the compressor has been switched off.
• Refer to the application guideline of each product range for first start-up recommendations.

Start-up

• Check the resistance according to the heater model (see table on page 1).
• Perform an insulation test before start-up.
• Check the voltage.
• Ensure the minimum oil superheat required by the compressor model is respected.

Important Notes

• Modifications or alterations of this product are not allowed.
• The goal of these heaters is to prevent refrigerant migration during off-cycle periods.
• The lead wires of the heating belts with 3 lead wires shall not be cut (as they are made of glass fiber).
• Note: An appropriate oil temperature should be maintained under all ambient conditions (temperature and wind). However, below -5°C ambient temperature and a wind speed of above 5 m/s, it is recommended that the heaters be thermally insulated to limit surrounding energy losses.

Diagram Descriptions

• Fig. 1: Illustration showing the optimum location area for the crankcase heater on a compressor, indicating approximately 1/2 h and 1/3 h from the bottom.
• Fig. 2: Diagram showing the installation of the crankcase heater around the compressor, highlighting the clip and screw for securing it.
• Fig. 3: Image displaying the crankcase heater unit itself, showing its form factor.
• Fig. 4: Illustration demonstrating the placement of the crankcase heater on the compressor, showing it fitted around the base.
• Fig. 5: Close-up view of the securing mechanism for the crankcase heater, showing the clip and the screw to be tightened.