Cap tube length for R404a prom?

[CodeRed]

Guys,
I finally found an a/c tech that I have enough confidence in to do the R404a conversion of my prom. I plan to go ahead in a couple of weeks, but just want a few opinions (facts) about the conversion just to make sure this guy gets the numbers right.

Firstly, how much R404a? I have heard 40 - 44 grams and also have heard 80 - 100 grams. Whats correct?

Secondly, whats the optimum capilliary tube diameter and length for R404a?

Thirdly, I am thinking that the compressor and condensor may need a little more cooling (hint bigger fans). Any thoughts on this?

Lastly, has anyone had any probs due to the extra pressure (250psi). I heard that some proms had soldered not brased joints and I dont really wont to blow something apart.

Cheers

[bowman1964]

use tha cap tubing you have.the small increase in flow you will get will help you.
now i think if you search you will find the charge amount listed as it has been done.
but if you are taking to a ac tech he will charge by pressure gauges and superheat amount.if i worked on it i could care less what the actual charge is.because i would first brase new charge ports onto the unit.then vacuum it down to 28" .then charge the unit in the pc.i would give it a small charge at first and then once it is cooling i would set the actual freon amount by the superheat and pressure and actuall load temp.
this unit should if done correctly, increase the condensor temp from the compressor so you will need a better fan.i dont think the compressor will take a very noticeable increase in temp.

[CodeRed]

Originally posted by bowman1964
use tha cap tubing you have.the small increase in flow you will get will help you.
now i think if you search you will find the charge amount listed as it has been done.
but if you are taking to a ac tech he will charge by pressure gauges and superheat amount.if i worked on it i could care less what the actual charge is.because i would first brase new charge ports onto the unit.then vacuum it down to 28" .then charge the unit in the pc.i would give it a small charge at first and then once it is cooling i would set the actual freon amount by the superheat and pressure and actuall load temp.
this unit should if done correctly, increase the condensor temp from the compressor so you will need a better fan.i dont think the compressor will take a very noticeable increase in temp.

bowman,
the method you describe to get the correct charge is exactly what he described to me on the phone except he wanted to do it unloaded. It worries me a little to have someone play with prom whilst my CPU is running .. one mistake and boom there goes my cpu. I guess the overtemp protection might save me if something goes wrong :eek:

so u suggest to use the existing cap tube?

[bowman1964]

Originally posted by CodeRed
bowman,
the method you describe to get the correct charge is exactly what he described to me on the phone except he wanted to do it unloaded. It worries me a little to have someone play with prom whilst my CPU is running .. one mistake and boom there goes my cpu. I guess the overtemp protection might save me if something goes wrong :eek:

so u suggest to use the existing cap tube?

yes leave the cap tube.
now charging it unloaded will not give you the best temps.and dont worry set the cpu to 500mhz under max and let him charge it.you should be at least cooling -30c while he is charging it. the unit will cut off if it starts to heat.but i am telling you, if charged while under a load you will drop you temps by 10c.

[CodeRed]

thanks, I'll give it a shot as you suggest.