People get carried away with the sight glass thing. It is borderline useful on a TXV system, and utterly useless on a cap tube system. Whatsmore some systems should have solid liquid and some should not.
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People get carried away with the sight glass thing. It is borderline useful on a TXV system, and utterly useless on a cap tube system. Whatsmore some systems should have solid liquid and some should not.
And under some conditions a cap tube will have solid liquid and at others no liquid at all.
Compressor is 1/4HP LBP, unfortunetely i cant find any smaller cap tube.
Gary would it be better for solid liquid in the cap entrance ? why spray useless vapour in the evaporator?The vapour wont cool anything and it will raise (a little) the suction pressure.
i doupt if the vapour entering the cap tube can be liquified in its way inside the cap tube even if it runs inside the suction line.
I got a hundred feet of cap tube 0.026 where u at... pm me....
HAs anyone seen GARY ????
nadda
I'm not 100% sure, but I though I saw a post from him @ the other place more recent than here....
I remember awhile ago he said that he had some real life issues he needed to concentrate on.
I wonder whats up with Gary too!Quote:
Originally Posted by chilly1
Have you asked runmc whats up with him? Maybe he knows!
Personal things took Gary away from us.. quite long time was passed since he disappeared
I read a lot of gary's posts, hope he is alright.
I dont quite understand this. I would think that it would have no more impact on the efficiency than any other piece of pipe in the system. Also, starting my first build, I would like to use it just to make sure the system is dry and for the visual indicator that the refrigerant is condencing. How much efficiency am I loosing if I use it?Quote:
you don't want to use a sight glass on a captube system it acts as a small reciever and will reduce effeciency.
Practically none if you dont oversize it.
Actually the refrigerant condenses mostly in the capillary tube so aliquid full sightglass and the system will be overcharges. In a capillary tube system we use a simple liquid line temperature test to determine proper charge.Quote:
Originally Posted by labrat23
I have a question for chilly1 or someone else who uses low temp refrigerants: How much capillary tubing would you use for refrigerants like ethlylene? Co2? R-14? Or would you have to use a TXV?
Thanks chilly. I dont have a large supply of refrigerant, so I'll be keeping the overcharging/unnecessary charging to a minimum.
Depends upon your configuration. For ethlyene I use 60 inches of 0.040 when I am using a TXV first stage and want 250 watt load at -85C stableQuote:
Originally Posted by MutantToad
If I want colder I lengthen it. For -100C I use 75 inches of 0.040
R14 I use the same, I DOnt use Co2 in cascades.
Keep in mind these sizes also need to have teh captube subcooled properly for stability and static charges will be in the 180 to 200 PSI range. This will give you enough Refrigerant mass inteh system to provide proper flow so the compressors will not over heat.
Chilly do these systems operate different than a normal system?if so is it because of the small evap? refrigerant is condensed in the condensor and goes into the liquid line to the cap tube. Cap tubes are susposed to have a liquid seal to operate properly.Any thing I have ever worked on never condensed refrigerant in the cap tube.
Well most systems including hose hold refrigerators will throttle a mix of gas and refrigerant in teh capillary tube this is a kind of self metering system when properly charged.
EXP. A system charged to a solid liquid stream the capillary tube is not attached to the suction system. Flow is dependant upon room and cabinet temperature only.
EXP2 A system has a capillary tube attached to the suction line and is charged with both gas and liquid entering the capillary tube. The capillary is cooled by the suction so the gas condenses to a liquid and this is dependant upon how cold the cabinet is. As the suction line gets colder there is a longer liquid stream in the capillary. This increases the static pressure in the capillary lowering the flow causing the suction line to warm slightly. In this way the system achieves static balance.
every system i work on condenses the refrigerant to liquid in the condensor, it is sub-cooled by a few degrees before it leaves the condensor, it is completly liquid in the liquid line.then it goes to the cap tube. my understanding is it travels about 2/3 down the cap tube before it start to vaporrize from the low pressure acting on it. the cap tube meters the refrigerant,it does not condense there in a normaly system.
Hey, I was wondering how long of a cap tube I would require with ~280W to ~310W heat load? The gas is R404a. The reason I ask is if I try to calculate my length with the "forumula" you gave then I either wind up in the negative or something quite close. Thanks a lot, - Peter.
Can people please post some experience with 0.031 captube here.
The rule in the 1st post by gary says multiply by 1.6 but you then end up with something crazy like 5+ metres for almost any load.
Personally I find best results around 2.8 - 3 metres sofar
I am planning to use 4 m of 0.031 for 200w of heat load.
Im not sure but I think thats way too long especially for a 200watt heatload. I had 3.5 on my gpu unit charged for 100 watts and it was too long, since I made it 2.8 metres results are great.
If it was me Id use 2.5metres for that heatload, I know it doesnt make sense and is half the length of what this thread suggests I think it will work better.
This was all using 404a, and I still struggled to get good results.
Can Chilly1 please comment on this post...
you guys can't calculate very well I think :D
200 watt r404a/r507 gary's rule states:
3 meter for 150 watt of 0.028. 200-150=50. 50/15= 3 1/3. 3 1/3*30=100cm shorter. So that's 2 meter of 0.028 for 200watt. 2*1.6=3.2 meter of 0.031" for 200watt!
Well build a system put 200 W with that length of cap tubing for 0.031.... see if it can even hold load..... The 1.6 is widely acknowledged rules yes... but that is moving from one idealistic to another idealistic condition. I've seen different result in real life testing.Quote:
Originally Posted by Unknown_road