Want to know about Danfoss TXV installation instructions? If your answer is yes, then spend here a little bit of your valuable time. This blog describes how to install Danfoss expansion valve in refrigeration and air conditioning systems or heat pumps or other refrigeration equipment.
Danfoss Thermostatic Expansion Valve Installation Instructions
Danfoss thermostatic expansion valves (TXVs) are designed to calculate the refrigerant at the correct rate in the cooling coil. This will keep the proper dose of refrigerant entering the cooling coil for full air conditioning or heat pump system operating efficiency. Now, check our Danfoss expansion valve installation manual.
You should clean the expansion valve fittings and parts thoroughly before soldering or brazing in order to prevent debris from entering the refrigerant system. Moreover, you have to take the responsibility of protecting the TXV from heat which occurred during brazing or soldering by wrapping the valve body. Cover head with a wet cloth to give 1/4" to 1/2" of thermal protection. Maintain the distance between the soldering/ brazing torch and the expansion valve.
Don't use excessive solder or flux because excessive flow may enter into the valve or tube that prevents proper operation.
TXV Sensor Bulb
The sensing bulb of a thermostatic expansion valve that controls the valve clamped to the refrigerant suction line where it monitors the temperature of the device.
Install thermostatic expansion valve as close as possible to the heat pump or air conditioning evaporator coil inlet. However, the valve needs to install in the liquid refrigerant line ahead of the cooling coil.
You should connect the equalizing pressure line to the suction line immediately after the sensing bulb that operates TEV for valves which use external pressure equalization feature.
For a small refrigerant suction line like on a residential cooling system or heat pump, the sensing bulb is located on the suction line top. If that sensor bulb is clamped outside of the refrigerated space, then you have to provide additional protection from ambient temperatures. You have to extend the insulation minimum of one foot on both sides of the suction line where the sensing bulb is clamped.
Generally, on commercial HVACR refrigerant systems that use a larger diameter line, the TEV sensor bulb is located at the 5'o clock or 7'o clock position (i.e., on the lower portion of the suction line). Place the temperature sensing bulb close to the above level of the liquid refrigerant line. So, for larger diameters better to choose the 2, 3, or 4'o clock, and small diameter tubing 1'o clock position is best.
When you clamp the sensor bulb on the bottom of the evaporator line, the oil will act as an insulator traveling along with the bottom of the tube that results in the bulb doesn't give accurate temperatures.
On a multi-evaporator cooling or heat pump system, each expansion valve needs to install at a refrigerant suction line that indicates individual evaporator conditions. You should not install on the common suction line where multiple evaporators are connected.
Danfoss Expansion Valve Adjustment
Manually adjustable Danfoss TR6 expansion valve allows the system to set to always maintain the proper refrigerant level entering the cooling coil. So, to change as per your requirements here is how to set adjustable TXVs.
- These valves designed with an adjusting stem that can turn with a screwdriver. Some TEVs will require that first remove cap to get access for adjusting screw or stem.
- To prevent over adjustment, you have to turn the adjusting screw once at a time.
- For increasing the superheat setting, need to turn the valve stem clockwise. By turning the stem "in" or "clockwise" position, you can increase the pressure on the spring.
- On a Danfoss T/ TE2 valve, one complete rotation of the adjusting spindle gives you about 4K in the superheat at an evaporating temperature of 0°C.
- For the Danfoss TE5 expansion valve, one turn provides about 0.5K in superheat at an evaporating temperature of 0°C.
- On a Danfoss TUB or TUA valve, at an evaporating temperature 0°C, one complete turn of the spindle provides a 3K temperature change in superheat.
- To decrease the superheat setting, you have to turn the valve stem counter-clockwise. The normal range to set the TEV is 7 to 12 degrees of superheat across the evaporator coil.
- You should allow the heat pump system or AC to stabilize for half an hour after each adjustment turn before adjusting the valve next time.
When a thermal expansion valve installed we need a powerful compressor motor since the compressor has to start against head pressure. The system using a cap tube there is no device to close the complete refrigerant piping between the high and low sides of the unit. For this purpose, you will require an orifice. So, based on the capacity, your Danfoss expansion valve orifice selection needs to be done.
For the 44 TXV equalizer line installation, you can choose the downstream location from the sensing bulb. This ensures the correct pressure is signaled to the valve. In some situations, this location may not work.
Therefore select the right Danfoss thermostatic expansion valve for your refrigerant system based on the size of the metering orifice in the device. After getting the valve, follow the above-provided instructions in the Danfoss expansion valve installation manual. Stay in touch with us for more HVACR components installation tips.