Filter driers are designed to remove foreign materials, such as moisture, dirt, sandpaper grit, soldering flux, small solder beads, and acid from a refrigeration or air conditioning system. However, filter driers are notorious for becoming restricted from moisture, sludge, dirt, or oil that has entered the system from a poor service practice or extreme operating conditions.
Diagnosing an air conditioning system isn’t easy. A service technician must be a trained professional to diagnose a system efficiently and correctly — no longer can a tech rely on rules of thumb for coil temperatures or pressures.
Compressor performance curves can provide a service technician with the Btu pumping rate (capacity), mass flow rates, operating amperage, and operating wattage of a compressor when the suction pressure and head pressure are known for the system.
A refrigeration system’s compression or pressure ratio is defined as the absolute discharge pressure divided by the absolute suction pressure. Calculating this ratio can be a big help when it comes to troubleshooting a system.
Last month’s article covered a 400-series refrigerant blend’s total temperature glide, effective temperature glide, fractionation, superheat, subcooling, and average evaporator and condensing temperatures using a pressure/temperature chart. This article deals with system pressure drops and net temperature glide in a refrigeration and/or air conditioning system.
System design, performance, and service conditions must be evaluated when retrofitting with a zeotropic or near-azeotropic refrigerant blend. Always follow the refrigerant manufacturer’s retrofit guidelines before retrofitting with any refrigerant, or system performance could be affected and/or injury may occur.
Using variable frequency drives (VFDs) to control the speed of a compressor can provide improved occupant comfort and quieter operation in air conditioning and heat pump applications. Always consult with the specific compressor manufacturer before using a VFD controller on any compressor.
In this issue, we cover ductless products for the commercial market. We also look at alternative refrigerants and trends in R-22 reclamation. Other topics include a summer forecast, business franchises, and more.
Check back for additional content throughout the week.