Refrigerants:
There is confusion, fear, and uncertainty of which refrigerant the industry will choose. Win the race to zero GWP commercial AC products.
The spool compressor is compatible with a broad range of low-high pressure refrigerants. TORAD’s recent development focus on air-conditioning applications with low-GWP refrigerants such as R513A and near-zero GWP refrigerants such as R1234ze. TORAD has done substantial development and testing using R134a as it is easily available and low cost. TORAD also tests using R1234ze.
Near-Zero GWP
Air-Conditioning
TORAD is working diligently to introduce its technology optimized on near-zero GWP refrigerant R1234ze. Taking into account toxicity, ODP, GWP, flammability, cycle efficiency, operating pressures and cost, TORAD believes the spool compressor utilizing R1234ze is the future-proof solution. The spool compressor’s architecture is well suited for applications utilizing low density gas due to its high displacement density and low cost to manufacture.
TORAD’s spool compressor with R1234ze has achieved EERs within 2.5% of a similarly operating R410A scroll. R1234ze is a low pressure/low density refrigerant. Thus, to achieve the same cooling capacity of an R410A based compressor the R1234ze based compressor flow rate must be increased 2.5 times.
Applications/
Efficiency
TORAD has design the spool compressor to be flexible for multiple applications. TORAD’s current focus is on commercial air-conditioning between 22 kW (7.5 tonR) and 350 kW (100 tonR). TORAD is now testing R1234ze with a 105kW (30 tonR) prototype spool compressor originally designed for use with R134a. No modifications have been made to this R134a prototype to optimize for R1234ze. Preliminary test results show the expected reduction in capacity of 22% (based on the lower density of the gas), but a reduction in overall isentropic efficiency of only 1.8 points at typical air-cooled chiller conditions. TORAD’s technical analysis projects its next generation semi-hermetic compressor designed specifically for R1234ze will have favorable EERs.