Help evaluate my single stage rebuild

[Theo404]

I tested my newly reconstructed single stager yesterday and today, but unfortunatly I've managed to lose my thermocouple so I have no idea about evap temps, and had only what my motherboard (DFI SLI-D) told me was the core temperature. After tunning for an hour or so, I reached a rough 'good charge' and did a little controled test, for reference after I modify things. I'm going to modify things because the temps I saw didnt impress me. After tunning, a 15 min run of prime with the chip at 2.8 with 1.50V (couldnt do that before) the core temperature reached 1c.

Can anyone tell me what sort of core temps their DFIs report? and in relation to what evap temps.

Another thing that I wasnt very happy about was the temperature of the compressor, it was so hot that it was impossible to hold your hand on it for more than a second. I had this with my last system, but put it down to the compressor being to powerful for the tiny system it was attached to. It was a 1HP rotary, where as this is just a little less than 1/2HP (the dehumidifier it came frome consumed 380W, and all that was in it was the compressor and a fan which consumed about 10-15W. That makes just about 1/2HP by my calculations).

What sort of temperatures the compressors in other peoples systems get to? And does anyone have an idea what might be making mine so hot?

So I think my first attempt at improvement will be to change the length of capillary tube. Currently it had just over 2 metres of .031". I think I should make it longer. As the old rough 'guide' by gary at phasechange.com would calculate that for an estimated 150W load I would need 4.3m. I think this is a bit much really, so I was thinking about adding another metre and a half, to make 3.5m total. What do people think?

System specs:
1/2HP (origninaly for R134a) compressor
largeish condenser with two slow 120mm fans on
R290
2m of .031" cap

Any input is greatly welcomed!

Unfortunatly due to my current lack of a thermocouple I cant take the myriad of temp reading required to compleatly troubleshoot the system, but I think I will pick one up tomorrow and so I can get the figures.

[Theo404]

No one then?

[wdrzal]

Without giving temps and pressures anything said would just be a guess at best.thats why nobody responded, sorry

[runmc]

11.5 ft is too long for .031. I'm using right around 8ft.

Also I agree with Walt. You need gauge pressures and temperatures before anyone can help you.

[wdrzal]

2 meters is about 79 inches....7'7" not 11-1/2'

1 meter is 39.37 inches

[Theo404]

I see, apologies for the lack of crucial information. I'm still lacking my thermocouple, damn stupid UK market, there is not a single local store that stocks em.

Well I added the extra 1.5m of cap, to make a total of 3.5, and the system is producing lower temps. After 15min of prime at 2800mhz at 1.50V the core temperature (as reported by MBM) reached 1C with 2m of cap. It now holds at -4/-5C.

At the charge used to get -4C to hold during prime the low side was at about 2psig and the high at 160psig.

Any idea about what generaly makes compressors run hot? I ran the system last night for 2 hours solid and the compressor was so hot you couldnt hold your hand on it at all.

[wdrzal]

cool vapor returning does most of the cooling but compressors do require air also to be drawn over the can.

[gclg2000]

walt, ever seen/heard of compressor's w/ heatsinks on the shell to help disperse the heat better?