1. Introduction
This manual provides essential information for the safe and efficient installation, operation, and maintenance of the Danfoss 034N0082 Hot Gas Bypass Regulator. This device is designed for capacity control in refrigeration and air conditioning systems, ensuring stable evaporator pressure during periods of low load.
Please read this manual thoroughly before installing or operating the regulator to ensure proper function and to prevent damage or injury.
2. Safety Information
Always observe general safety precautions when working with refrigeration systems and components. Only qualified personnel should install, service, or troubleshoot this equipment.
- Pressure Safety: Refrigeration systems operate under high pressure. Ensure the system is depressurized before attempting any installation or service.
- Refrigerant Handling: Handle refrigerants with care. Always wear appropriate personal protective equipment (PPE), including safety glasses and gloves.
- Electrical Safety: Disconnect all power to the system before working on any electrical components.
- Proper Tools: Use only appropriate tools for installation and maintenance.
- Leak Detection: After installation, always perform a thorough leak test to ensure system integrity.
3. Product Overview
The Danfoss 034N0082 is a CPCE series hot gas bypass regulator designed to maintain a constant evaporator pressure by bypassing hot gas from the discharge side of the compressor to the evaporator inlet. This prevents evaporator icing and ensures stable operation during low-load conditions.

Figure 3.1: The Danfoss 034N0082 Hot Gas Bypass Regulator shown alongside its cardboard packaging. The packaging features the Danfoss logo and product identification labels, indicating the model number and capacity.

Figure 3.2: A detailed close-up of the regulator's label, clearly displaying "REFRIGERANT HOT-GAS BYPASS REGULATOR", "Type CPCE", and "RANGE 0-6 bar / 0-85 psig". This label provides critical operational parameters and identification.

Figure 3.3: A side profile view of the Danfoss 034N0082 regulator, highlighting its brass body and copper solder connections. The compact design and connection points are visible, indicating its readiness for integration into a refrigeration line.
4. Installation
Proper installation is crucial for the optimal performance and longevity of the hot gas bypass regulator. Follow these steps carefully:
- System Depressurization: Ensure the refrigeration system is completely depressurized and isolated before beginning installation.
- Location: Install the regulator in the hot gas line between the compressor discharge and the evaporator inlet. Ensure there is sufficient space for servicing.
- Flow Direction: Observe the flow arrow on the regulator body to ensure correct installation direction. Hot gas should flow into the regulator from the compressor side.
- Connection: The 034N0082 features 1/2" CPCE solder connections. Use appropriate soldering techniques and materials to create leak-free joints. Protect the valve body from excessive heat during soldering to prevent internal damage.
- Mounting: The regulator can be mounted in any position, but ensure it is securely supported to prevent vibration and stress on the piping.
- Leak Test: After installation, evacuate the system and perform a thorough leak test using an appropriate leak detection method.
- Refrigerant Charge: Recharge the system with the correct type and amount of refrigerant as specified by the system manufacturer.
5. Operation
The Danfoss 034N0082 Hot Gas Bypass Regulator operates automatically to maintain a minimum evaporator pressure. When the evaporator load decreases, the suction pressure tends to drop. The regulator senses this pressure drop and opens to allow hot gas from the compressor discharge to bypass directly into the evaporator inlet.
This injection of hot gas raises the evaporator pressure, preventing it from falling below the set point and thus avoiding evaporator icing and ensuring stable system operation. The regulator modulates its opening to precisely match the system's capacity requirements.
6. Maintenance
The Danfoss 034N0082 regulator is designed for long-term, reliable operation with minimal maintenance. However, regular system checks are recommended:
- Visual Inspection: Periodically inspect the regulator and surrounding piping for any signs of leaks, corrosion, or physical damage.
- Leak Checks: Include the regulator in routine system leak detection procedures.
- Performance Monitoring: Monitor system pressures and temperatures to ensure the regulator is maintaining the desired evaporator pressure. Significant deviations may indicate an issue with the regulator or other system components.
- Cleaning: Keep the exterior of the regulator clean and free from dust or debris.
Note: Internal components of the regulator are not user-serviceable. In case of malfunction, the unit should be replaced by a qualified technician.
7. Troubleshooting
This section provides guidance for common issues that may arise. Always ensure safety precautions are followed before attempting any troubleshooting.
| Problem | Possible Cause | Solution |
|---|---|---|
| Evaporator pressure too low / Icing | Regulator not opening or set point too low. Insufficient hot gas supply. | Check system charge. Verify regulator is installed correctly. If regulator is faulty, replace it. |
| Evaporator pressure too high / Overheating | Regulator stuck open or set point too high. | Check for debris in the valve. If regulator is faulty, replace it. |
| Leaks at connections | Improper soldering or damaged connections. | Locate leak using leak detector. Repair or re-solder connections. If valve body is cracked, replace unit. |
8. Specifications
| Attribute | Value |
|---|---|
| Model Number | 034N0082 |
| Product Type | Hot Gas Bypass Regulator |
| Connection Type | 1/2" CPCE Solder |
| Pressure Range | 0-6 bar / 0-85 psig |
| Maximum Working Pressure (MWP) | 312 psig |
| Compatible Refrigerants | R12, R22, R134a, R404A, R507, R407C, R410A |
| Manufacturer | Danfoss |
| Product Dimensions | 9 x 7 x 5 inches |
| Product Weight | 5 Pounds |
9. Warranty and Support
For specific warranty terms and conditions, please refer to the documentation provided with your purchase or contact the authorized Danfoss distributor or seller from whom the product was acquired. Warranty coverage typically applies to defects in materials and workmanship under normal use.
For technical support, product inquiries, or to locate an authorized service center, please visit the official Danfoss website or contact their customer service department. You can also find more information on the Danfoss Store on Amazon.





