First of all I would like to apologize myself for only asking questions and adding virtually nothing to this forum. I am simply too inexperienced to be able to give sensible answers to all the questions over here.

Well, a little update for the people who followed my earlier threads: Yesterday I have been able to buy an orifice 0X for the Danfoss TEN2 TEV (with 0 °C MOP point) I will use to replace the capillary tube in the next update of my water/methanol chiller (which works flawless at the moment; only the temp fails to drop below approximately -14 °C). I was also able to buy a filter/dryer with 1/4" ODF solder connections. Obtaining these parts costed me several months The Dutch government definitely doesn't want me to build my own refrigeration equipment. But I complained already enough about that. Also, the airtight mainboard box with a silicagel desiccant in it works flawless. I haven't seen any ice or condensation forming during all the time I have been using it. The processor itself is happily running at 2+ GHz.

Getting the system running with TEV should not be such a hard job. All I have to do is to thoroughly clean the inside of the evaporator piping, solder all the various parts together, pull a vacuum, and refill with R134a.

There are only a few hurdles left:

- I am unable to obtain a sufficiently small receiver. The smallest one I am able to obtain is a 5 dm3 one (with 1/2" liquid line connections). Way too large for my system. So, I have made myself a receiver from a 20cm piece of 1" pipe, capped on both sides, and 1/4" copper refrigerant inlets/outlet pipes mounted on one side. The refrigerant outlet runs down to the bottom of the 'receiver', so it draws liquid. This 'receiver' provides me with about 75cc (0.075 litres) of liquid refrigerant storage. Since the inner volume of the evaporator pipe is also small (115cc), I thought this very small size receiver would be sufficient. This assumption is based on the fact that the receiver contains more refrigerant in liquid form than what will fit in gaseous state in the evaporator. Thus, even at the highest operating temperature there will be liquid in the receiver, and the TEV will get a decent supply of liquid refrigerant under all operating conditions. Unfortunately I am at work now, and I have not brought my calculations with me.

Am I correct in these assumptions, and is the receiver sufficient?


- To be able to use my current compressor (Danfoss NL11F) with a TEV, I have to use another starting device. Normally this compressor is used in capillary tube systems, so a simple PTC based starting device can be used (LST: Low Starting Torque). This device only works when pressures at both sides of the compressor are approximately equal when starting the compressor. If there is a pressure difference, this starting device does not provide enough torque to allow the motor to start.
There exists another starting relay / start capacitor combination for this compressor, which produces a higher starting torque, and thus allow this compressor to be used with other expansion devices such as a TEV. The only problem is: I am, as usual, not able to obtain this High Starting Torque start device. Even worse: I cannot obtain information on how exactly this device works. I imagine that during start a start capacitor is placed between the start winding and the mains. This introduces a phase shift, which helps the rotor to rotate. After starting, I imagine that the start winding is switched off, and only the run winding of the motor stays energized.

Is temporary switching on the start winding with a series start capacitor indeed how those HST devices work? If so, I can build myself some electronics which does exactly the same. But: what value should the start capacitor be? And how easy is it to damage the start winding of the compressor? I definitely don't want to blow the compressor.