Where I worked on refer units with small diesel engines driving the compressor, at one time testing Evans coolant as a possible replacement for ethylene glycol based coolant. Looking through some notes from the chemist. Most of the Evans was propylene glycol. The reason it was considered is it did not contain phosphates or silicates. Europe had ruled out phosphates and China ruled out silicates in engine coolants, so it was tested. The Evans never received engineering approval. One problem noted was the viscosity of the Evans reduced the coolant flow rate about 20% at the operating load of engine, (in this case a 4 cylinder Kubota diesel) and reduced heat transfer to the radiator. So the conclusions were a radiator of larger capacity and a higher flow water pump would be required for use. The decision on coolant at that time was to go with Dexcool, which ended up with that mess of corrosion problems.
