A few things here that I would like to comment on.
Firstly the use of capillary verses TX valve. There are approx. 60million domestic refrigerators built each year and nearly all are capillary and a great many, specially in developing countries, operate in varying environments some extreme. The issue with capillary throttling is that the required capillary orifice / length needed for optimum performance
varies dramatically with a change of condensing temperature. (And other factors to a much lesser degree) For example an 80 watt system with -15c evaporator and 45C condenser would ideally use 3.18 Meters of 0.80 capillary but this would need to be nearly doubled if the condensing temperature reached 55C. Now altering the capillary size is not possible whereas a TX valve will vary its orifice opening to compensate somewhat but they have other issues.
At Ozefridge we use capillary and address the issue by maintaining our condenser temperature within desired parameters therefore providing optimum performance without the possibility of over or under condensing regardless of how hot or cold the environment
is and without the need of a TX valve and receiver. Our system operates as follows to maintain a constant condensing temperature:
Upon a cycle start up the twin fans operate at half speed once the condenser temperature reaches 35C. This occurs quickly but avoids any possibility of over condensing as mentioned by an earlier poster. When / if the condenser temperature reaches 43C the fans switch to full speed and the one third amp water pump id powered on. The fans revert to slow and the pump is switched off once the condenser temp lowers to 38C. This maintains our condensing within our engineered range at all times.
(As a side issue we found that R134a used through a capillary without controlled
condensing temperature, often builds a restriction at the capillary outlet!)
Regards water cooling: Our water cooling method complements the air cooling and the AW models can operate as either, and as described above the water function is controlled. Water cooling is the answer for those who have no well ventilated and dry area for the condensing unit, or those looking for optimum efficiency and performance specially in hotter environments. Absorption and dissipation rates of heat via water is far greater than air.