need help with my new dod(pls)

[RockfordFosgate]

hi to all im using my firends account now but i have a problem with my dod(i think) first of all i want to write my compoments...

danfoss 1/4 r22 hermetic type compressor(nl9)
1/6 2.75m cap
30gr dryer
chilly1 blocks
2x 20x20x5 condenser

its sth like this (sorry about bad pic)
http://img404.imageshack.us/img404/7272/10032007120co2.jpg

how much r22 gaz do i need to put in it and now the evap is -36C celcius... i think its not good at idle...do i need to adjust the gas in load or in unload?and what must be the min. and max. bar's of r22 in load?

[LukeXE]

Hello, welcome on XS :toast:

First, explain for me, in milimeters, what diamater has that 1/6 captube.
Second, It`s hard to say how much exacly gas you need in your system, it depends on a lot of things.

Tell me at what pressure (suction/discharge) you`ve got that -36*c idle.

Cheers

[RockfordFosgate]

i dont really know the exact mm of captube...
and i'm new at dd for now thats because there could be lots of faults:P
http://img144.imageshack.us/img144/2058/10032007120co2ua9.jpg

and for te captube i found that site but i couldnt find 1/6 :S
http://mdmetric.com/tech/cvtcht.htm


thanx again...

[LukeXE]

Woah...from what I see you`re using about 4mm captube ! that`s too big !

Buy 1/32 captube (~0,8mm) and then use 2,75m of it. Your is too big, with new one you will get much better results.

[RockfordFosgate]

now i put my hair dryer for a bit load testing and the temps went down like
-19C and didnt changed for 1 hours...
i think i will take the worst dod prize =)

[RockfordFosgate]

no i its not=) when i look from here the outside diameter is about 1.2mm but i cannot really know the inside dia...

[LukeXE]

If that 1/6" is really about 4mm (25,4mm/6), you would need around...don`t wanna guess, but about 15m not 2,75m...

With 1/32 captube 2,75m length will be ideal for that kind of unit, maybe even 2,8m.

So captube is problem in your unit ;) Cheers

EDIT@

So what size is that captube ? not 1/6 still ?

[RockfordFosgate]

no i think its not with " because when i look from here its around 1.2mm outside diameter...

[LukeXE]

So sorry, I still thinked that you have 1/6" captube. try to use about 3,4m of your captube, maybe it will help.

[RockfordFosgate]

thanx @luke now i phoned to my friend who sells that sort of things and he said to me that 1/6 captube means 0.7-0.8mm...now i think there is another problem?in the plastic bag of captube the on the label i found that there is written 0.75-0.85mm...

[Gray Mole]

I had a feeling your captube wasn't that big.

-36c isn't great for a result even with R22, but it's not that bad either.

It boils around -40 at 0psig, so you are likely seeing a slight pressure over that.

You're also not insulated so you're not going to be reading a completely 'no load' situation.

You have no U-Bend or accumulator, so you could end up with liquid/oil floodback quite easily, as you have nothing forcing the leftover refrigerant to evaporate, and no way to slow up the return of oil at all.

An NL9 Danfoss, with R22, could do well at about that temperature, with that captube length, in terms of load.

However, a hairdryer isn't going to give you any idea of any real load either. No way to judge it.

So at this point, insulate properly, and find something to load test with.

You could do so on a PC if you like, and just tune it for best temp at highest load you can put out.

There are a few changes I would make but for a first attempt it's not really that bad. It works. Now give it a try on something whether a proper load tester or a cpu, and do the tuning 'live' if you want to be sure about loads and performance.

Cheers

Gray

[RockfordFosgate]

thanx gray its my first try whatever i will try it now im insulating all...

[RockfordFosgate]

what about to add some co2 inside? could it be good or it would make worser?



thanx to all for replying...

[Gray Mole]

For now, I wouldn't bother trying to work with any kind of blend, much less CO2. That's a high pressure gas, and is only recommended for Auto or Cascade use. There are occasions when people have successfully used it in a single stage, but they have taken into account it's nature and built the system to work with it.

Until you have built a few singles, and refined your technique and mastered some of the various methods, I would say to keep working with the standard single stage gasses for now.

I would recommend, if you want to know how well your system will perform to at least buy/build a basic load tester. Even a fixed resistor giving 150-200 watts will be very useful in setting things up prior to use on a cpu.

Gray

[RockfordFosgate]

now i found a resistor i think its around 150 watt and my temps are now -29C in load...is that good?(for first single stage of course) =)

[LukeXE]

Very good result

[RockfordFosgate]

thanx Lukexe at the end i reached to 32C at load of 150w and idle of 40C...

thank too all of you for helping me...

[RockfordFosgate]

today i tried with my hair dryer (they wrote 1800 watt) and the temps was went down like -10C after 5 min. i reached to -18C but they have written 1800watt but how much watt could it give with the hair flow?


thanx for repyling
sorry for my bad english...

[[XC] MarioMaster]

well like Gray has said, using a hairdryer as a load tester really isn't a good idea since there's no real way to measure how much heat is going into the evap, not to mention it's not really loading the evap the same way a CPU would, but from the results you're getting your result is quite good for a first system.