How does the APR Control work?
The APR Control provides continuous capacity modulation on direct expansion air conditioning and refrigeration systems. Contractors, Distributors, and Engineers referred to the APR Control as hot gas bypass because it was the easiest way to remember and explain application use. However, the APR Control is NOT hot gas bypass! (Check out our recent whitepaper)
The difference is that the APR Control is better than hot gas bypass! For 30 years, the APR Control has proven to be superior to hot gas bypass because of its performance in humidity control, compressor protection, and ease of installation. There is also the major advantage of reducing power consumption, optimizing energy performance and efficiency.
How does hot gas bypass work?
Traditional hot gas bypass creates a false load in the evaporator, usually eliminating the latent capacity of the evaporator coil. While by contrast, the APR Control diverts refrigerant around the compressor and back into the suction line. This reduces power consumption while increasing latent heat removal capacity. Contractors across the country have reaped the benefits of utilizing the APR Control on packaged equipment, splits, heat pumps, VAV, MUA, and any other DX system in need of capacity modulation; often discovering how much easier Rawal Devices’ APR Control makes providing capacity modulation when compared to hot gas bypass.
Using hot gas bypass on some of these systems is difficult, if not outright impossible. It is also likely to fatigue the compressor under many conditions. High modulation rates can cause compressor overheating. Hot gas bypass requires the addition of a third line on split systems. And today’s micro-channel condenser coils can’t handle the additional refrigerant charge that traditional hot gas bypass requires (traditional hot gas bypass is routed to the entrance of the evaporator coil). The hot gas line requires more refrigerant charge and thorough insulation unless you intend to create an alternative liquid line or liquid receiver. We constantly field calls where a service technician has come across a hot gas line that may be as much as 100ft in length or longer, causing compressor reliability issues.
APR Control is the better solution
The APR Control is simple, effective, and reliable with a minimal inconvenience. Rawal Devices engineering staff asks for vital information about circuiting, staging, and suction line size to ensure proper sizing of the APR Control! Rawal Devices Customer Support will help you size and select the proper APR Control for the amount of modulation your system may need.
