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Both high and low drop to zero

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#21 ·
jactechcool said:
I think we found the problem :). Temps across the filter dryer.

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So my question is why was there still all that junk in the system? What did you do to try to get it out before you put the new compressor in?

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#23 ·
jactechcool said:
Yea, it’s a little 3/8 catch all. The system had no filter from the factory so added this one in. Before you ask, yes it’s installed in the correct direction.

—john


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It shows some balls that you have not taken offence to "our" advice and opinions, GOOD MAN!!!!!!!! In the past others have threatened us w/ their "lack of staying here" because of our attitudes and language.

What size LLFD is a "little 3/8 Catch All" ? Thats like saying "all press/temp readings are good/normal".
 
Discussion starter · #27 ·
Nada on the suction line. In fact, factory stock there was no dryer on the unit at all. Spoke with a friend who works on these machines for telcom industry. He said every time hes tried to add a filter dryer, same issue. No need to reply with "Well then theres an issue in the lines thats causing that". I would think so too.

Anywaysssssssss

I poped out the dryer i put in, eliminated it. Put the thing together.

10 mins later im getting 17 deg superheat and its running perfectly.

Whats really cool is i learned a lot from this unit....im almost happy i ran into so many issues since that taught me a lot. And i still made money on the deal since i sold the one for so much =).

And yea, i never get offended...just always listen to advice!

--John
 
#28 ·
jactechcool said:
Nada on the suction line. In fact, factory stock there was no dryer on the unit at all. Spoke with a friend who works on these machines for telcom industry. He said every time hes tried to add a filter dryer, same issue. No need to reply with "Well then theres an issue in the lines thats causing that". I would think so too.

Anywaysssssssss

I poped out the dryer i put in, eliminated it. Put the thing together.

10 mins later im getting 17 deg superheat and its running perfectly.

Whats really cool is i learned a lot from this unit....im almost happy i ran into so many issues since that taught me a lot. And i still made money on the deal since i sold the one for so much =).

And yea, i never get offended...just always listen to advice!

--John
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Can you explain the things that you learned? I found that if you figure out how to clearly explain something often you will understand it better yourself. There's a saying something like if you can't explain it in simple terms then you don't understand it well enough.

PS I'm listening.
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#29 ·
jactechcool said:
I poped out the dryer i put in, eliminated it. Put the thing together.

10 mins later im getting 17 deg superheat and its running perfectly.
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that makes zero sense ...

Well , unless the drier was clogged up , and seeing that 30 degree split across the drier certainly points to a clog
 
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Discussion starter · #30 ·
Good idea, explanation:

It all makes total sense:

System is like this: Compressor ---> Condenser ---> Dryer i installed ---> High Side Process tube ---> evap cap tubes ---> evap ---> Low side process tube ---> Back to Compressor

1. Filter Dryer i installed clogged...i dont know why, i havent cut it open yet. Im thinking junk from the old compressor.
2. Once it was clogged it let very little refrigerant or anything flow forward of it.
So High side gauge would read almost zero...since tube is after filter...there was little pressure in the high side at that point in the system.
In reality, before the filter, there was good pressure, but the process tube isnt there, so i didnt see it.

3. Don't know why i didnt think of it right away, i put thermocouples on the tubes on both sides of the filter. Pressure=Temp! Saw the massive temp difference between going in and coming out, so i now knew there was a large pressure drop in the filter. *Knew about this test, but never had to do it...now i will never forget*

--John
 
#31 ·
jactechcool said:
Good idea, explanation:

It all makes total sense:

System is like this: Compressor ---> Condenser ---> Dryer i installed ---> High Side Process tube ---> evap cap tubes ---> evap ---> Low side process tube ---> Back to Compressor

1. Filter Dryer i installed clogged...i dont know why, i havent cut it open yet. Im thinking junk from the old compressor.
2. Once it was clogged it let very little refrigerant or anything flow forward of it.
So High side gauge would read almost zero...since tube is after filter...there was little pressure in the high side at that point in the system.
In reality, before the filter, there was good pressure, but the process tube isnt there, so i didnt see it.

3. Don't know why i didnt think of it right away, i put thermocouples on the tubes on both sides of the filter. Pressure=Temp! Saw the massive temp difference between going in and coming out, so i now knew there was a large pressure drop in the filter. *Knew about this test, but never had to do it...now i will never forget*

--John
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Next time will you actually need a thermometer to detect that bad of restriction?

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"Is this before or after you fired the parts cannon at it?" - senior tech
 
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#33 ·
jactechcool said:
Nada on the suction line. In fact, factory stock there was no dryer on the unit at all. Spoke with a friend who works on these machines for telcom industry. He said every time hes tried to add a filter dryer, same issue. No need to reply with "Well then theres an issue in the lines thats causing that". I would think so too.

Anywaysssssssss

I poped out the dryer i put in, eliminated it. Put the thing together.

10 mins later im getting 17 deg superheat and its running perfectly.

Whats really cool is i learned a lot from this unit....im almost happy i ran into so many issues since that taught me a lot. And i still made money on the deal since i sold the one for so much =).

And yea, i never get offended...just always listen to advice!

--John
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Someone is full of crap about those FD's. I install SLFD-HH in 80-90 % of comp change outs, I install LLFD-HH in 100% of comp changeouts w/o any adverse affects. So?

I have never seen a SLFD in any new piece of equipment.
 
#36 ·
If it is a Sanhua filter drier (Chinese) it may just be crap.
 
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Discussion starter · #37 ·
I agree. But I can’t argue with the results. On any system ive put one on, no issues. Except this one.

Wish I could say I did something else.

—john


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#38 ·
jactechcool said:
I agree. But I can’t argue with the results. On any system ive put one on, no issues. Except this one.

Wish I could say I did something else.

—john


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That just proves that the system is seriously dirty. Clogging up is no fault of the filter. The filter needs changed until the system stays clean and dry. This is why learning from experience is not a good idea without a good understanding of the theory's behind what you are doing and a good understanding of best practices.

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#39 ·
jactechcool said:
I agree. But I can’t argue with the results. On any system ive put one on, no issues. Except this one.

Wish I could say I did something else.

—john


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I'll take a SWAG (stupid wild ass guess) here. "IF" everything is as you say it is then I will say that the new LLFD was soldered/brazed shut and that there was very little debris in the system to begin with. Another lesson should be learned here. Read up on the basics of soldering/brazing.
 
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